Seat reservations on regional trains

I do not think I would even worry about it. The reservations are not mandatory, to be honest I do not think I ever paid attention on RB and RE trains as to whether a seat was reserved, these trains rarely sell out.

I've been on a lot of German trains without realizing you could make a seat reservation on regional trains!
As above, I've never had a regional train without plenty of free seats. I wouldn't bother with reservations.

As you may be aware, there are no reservations for seats except 1st class. Arrive early at the station and use the DB personnel at the ticket window. While buying tickets is easy at machines, other things not so much.

"As there is little time for changing trains, can these reservations be made at the Rothenburg station for the other trip segments?"

Time between trains depends on whether trains are on time, late, or early. Reservations don't help you catch a train. Reservations are available for the IC / ICE /other long-distance trains, not the regional trains. If you have a valid ticket you can board IC/ICE trains without a reservation. If every last seat is taken, you can stand and wait until someone gets off at the next stop.

Official info on seat reservations at Deutsche Bahn, see part "Seat reservations for regional trains" and "Trains on which ...".

there are no reservations for seats except 1st class.

That's not the way I read it. You can reserve seats in either the first or second class areas, but to reserve a ticket in the first class area of a train you must have a first class ticket. Reservations for regional trains are only €1, so why not.

It says you can reserve a seat at a ticket automat or a ticket counter. There are ticket automats in Rothenburg. There is also a ticket counter, but its hours are limited, starting at 10 AM.

It doesn't look like you can reserve seats online from the Bahn website (at least yet).

Why not reserve on regional trains? I can think of a reason or two.

The list of rail lines around Germany where RE/RB seat reservations are even possible at this point is exceedingly skimpy. Practically speaking, one can assume they don't exist.

Even if your target route happens to offer this service, you will still have to physically locate the specific car and seat where you are to sit - and board at the right segment of the platform (wonder whether the platform signage and train/car charts - the "Wagenstandanzeiger" - post info on the regional trains? Also wonder whether seat area signage on these trains will identify clearly any reserved seating?)

Also, if the train really is crowded, you will probably have to boot someone out of your seat... the riding public is simply not accustomed to reservations on these trains, not in the habit of checking seat signage before sitting - everyone thinks of them like the subway trains - they just find a seat and plop - and I wonder how (un)cooperative some riders will be at getting displaced.

Let's say you're a couple with reserved window seats facing each other. You board at the right location and locate both the right car and the right seats. The train isn't very full. But the seats adjacent to your reserved ones are both occupied. And, like most regional trains, space is a little tight, so your seated companions have their personal items (day bag, coat) on your reserved seats. Your bags are too thick to fit in the less-than-useful overhead rack that is commonly found in regional trains. And you don't want to make your bag grubby by putting it on the floor under your seat. Now, rather than deal with all those issues, wouldn't you prefer to just find a couple of empty seats elsewhere, where there's more room?? Wouldn't you wish you hadn't bothered fussing over that reservation? I sure would.

wonder whether the platform signage and train/car charts - the "Wagenstandanzeiger" - post info on the regional trains? Also wonder whether seat area signage on these trains will identify clearly any reserved seating?

No to both. Seat reservation on regional trains is useful for commuters, for the occasional traveller it's more cumbersome than useful.

The "Wagenstandanzeiger" does not apply to regional trains., the RE and RB. As far as I know, no seat reserations can be made in 2nd class. Making a seat reservation on the RE and RB may just apply to the small 1st class section.

I've been on a number of regional trains but not the connection listed above where no seats were available. A ton of people were on and you stand like everyone else when all the seats are taken, which does indeed happen.

Reserving a seat on a regional train does seem quite strange to me. I didn't believe it until I put in Rothenburg odT to Munich on the query page and saw the reservation possibility for two of the legs, and I went to the Bahn site and saw that they are starting to have reservations on selected trains. The two reservable legs on this connection are the Steinach to Treuchtlingen leg (1h06 and Augsburg to Munich (42 min). If either of those trains were full, standing that long would not be pleasant, and you would feel like a real fool for not taking advantage of the €1 reservation.

@Russ, per your hypothetical situation. You are assuming "The train isn't very full. But the seats adjacent to your reserved ones are both occupied", statistically an improbable situation. Anyway, just because you have reserved seats doesn't mean you have to sit in them. At €1 each, it wouldn't bother me a lot in the unlikely case that I found it inadvisable to use the reserved seats. if I found that the seats next to me were occupied, my 12# carryon will fit in the overhead rack (the advantage of packing light). Or, more likely, I'd sit it on my lap. In most cases, if I can't use the seat next to me, I'll hold it on my lap rather than put it on the floor or in the overhead rack. And if I didn't have a reservation and did have to stand, my bag would have to sit next to me on that grubby floor.

In 2008, I was on a commuter train out of Hannover on a Monday afternoon rush hour. The train was so crowded that not everyone with a ticket could get on. Some were left on the platform, others were standing in the door well, just inside the coach. I had to stand for close to an hour before enough people got off for me to find a seat. I would have given a lot more than €1 for a reserved seat that night, even if my bag did have to sit on the floor.

In 2008, I was on a commuter train out of Hannover on a Monday afternoon rush hour. The train was so crowded that not everyone with a ticket could get on.

Well, let's not dramatize. Steinach to Treuchtlingen is a whole different matter. At most times of the day, I'd rather expect to have my personal carriage (and I go there often). Augsburg to Munich trains are crowded at commuting times; at all other times there is no problem to find a seat. The reserved seats are not marked as such. So it's not unlikely that you will have to send someone away from your seat.

As far as I know, no seat reserations can be made in 2nd class. Making a seat reservation on the RE and RB may just apply to the small 1st class section.

As stated by others, this is not the case. In the (few) regional trains in which a seat can be reserved, that applies to first and second class. Source: I have done that.

Thanks, I stand corrected.