Grocery store near the Munich train station?

You mean the street south of the Haupftbahnoff.
It is Bayerstrassee
Store called Rewe is in walking distance
https://goo.gl/maps/rYdgrPFbu9n
https://en.wikipedia.org/wiki/REWE

Aldi's at Schwanthalerstrasse 14, Go south on Schillerstrasse and turn left on Schwanthalerstrasse.

I was going to suggest the Cafe Glockenspiel in the Rathausturm before you deleted that thread.

Sam--so you saw that first post about a breakfast place. After posting, I thought to check our reservation for the cost to add breakfast there. That is when I discovered I booked a studio with kitchen----precisely so we could sleep in late and have breakfast in the room. I had forgotten that---this is the trouble with reservations made long in advance. We are light eaters at breakfast so the full-on breakfast buffet is usually wasted on us, unless we have a full day of hiking ahead of us.

I'm a great fan of the European Egg McMuffin. Costs less there than at Mickey D's in the States.

There are a number of grocery stores at München Hbf., upstairs and downstairs, depending if you use the Bahnhofspassage or not....all new and elaborate.

I use "Yorma" for groceries, esp mineral water, located on the opposite side of Bayerstraße, ie Arnulfsstraße, since that side going down the stairs to Bahnhofspassage leads to almost directly to my Pension once I go up the stairs. The easiest way to spot out "Yorma" is that it is next to track , ie Gleis 26., the very last one.

I sometimes bring a small plastic bag of our favorite cereal/muesli with us to consume as we go. You can buy a small carton or milk or even those excellent German yogurts to eat in a bowl with your own cereal.

Thanks, Mona. We decided to bring out own cereal so all we will need is milk. Just need a convenience store nearby---hotel is on Schillerstrasse.

In most European countries Supermarket or Supermarkt (in German) is the word for grocery store. Just enter this on Google maps and you'll get all your answers including opening hours. "Supermarkt near Munich Hauptbahnhof" is the search phrase for Google maps in this instance - but it works for every place and all over Europe.

no mention of time or day of week. Shop opening hours are regulated in bavaria, few open Sundays and in many places some (probably not supermarkets) still follow the old rules and close on Saturday afternoons. Closing time is 8pm. But the good news is that there is a small Edeka store in the airport which is also exempt from the rules, and you will probably be going past it anyway! It's in the central service area, over the S-Bahn train platforms near the car hire desks and the doors out to terminal 2. Look for the yellow and blue E logo.

As mentioned by somebody else above there are several Supermarkets in the Munich Hbf. e.g. the Edeka, which is open till 11pm and the (smaller) Rewe, which is open around the clock.

We arrive at the airport at 7:30 pm on a Monday. We I'll take the S-Bahn to the Hauptbahnhof and hope a grocery in the station is still open. If not, we can just find a bottle of milk in the morning. The Aldi on Schwanthalerstrasse would be close. Isn't that the parent chain for the US Trader Joe's markets?

Thanks all for your help. We will be pretty tired when we arrive and I wanted to have a plan in advance.

Isn't that the parent chain for the US Trader Joe's markets?

No, that's Aldi Nord. Munich is obviously in the area of Aldi Süd (those are two related but different companies).