I just returned from a trip to the CR, and wanted to report back on a few things. I was with a non-RS tour group, but kept my Forum eyes on things to report on.
1. yes, too many tourists. Even our local guides commented on this. You could see groups (like ours) following their flags marching across the squares like armies. But really, this is in the popular touristed corridors, where tourist-shops and businesses are concentrated and all the workers speak english. The Charles Bridge was un-enjoyable, and there just aren't enough infrastructure, like WCs and benches to rest on, where needed because of it.
Clothes. Yes, everyone wears everything possible. As one in our group said, everyone dresses badly now, like Americans with no self-respect. :) But what our local guides pointed out, was that the majority of who we were seeing, were other tourists. Not locals. Outside of the tourist areas, locals dressed more conservatively. White shoes and jeans everywhere.
DCC. Tap worked everywhere. Unexpectedly, after multiple ATM and merchant transactions, I did not see DCC offered once.
All our transport and most restaurant transactions were covered by the tour, but I must say the food was great everywhere.
I'm going to make another post about outside Prague, but I will just say that I think one needs to visit more than just Prague if you go to the CR.