I think perhaps this question could have been worded better.
I don't "limit" my FM listening to any one room or system.
Granted, most of my FM listening is done on a two channel system because it's mostly later at night before falling asleep but, since my AVR is in the living room, I will listen to it ther just as readily if I'm in the mood and happen to be doing something there.
For instance, If I'm bouncing around the first floor (where the AVR resides, and a station is playing what I want to listen to (which most likely will be a Saturday or Sunday morning), I have no qualms about tuning it in on the AVR and enjoying the heck out of it.