There are two shops in town for me. I was certified in one, but I've dropped in on the other on occasion (generally to give them a chance to sell me something that my "home" LDS doesn't carry or have in stock). They certainly aren't rude or mean or anything, but I've never really felt welcome there.
On the other hand, long before I was even certified, I dropped in on what is now "my" shop just to see what it was all about. I almost felt bad because they were treating me so well when I knew (and had told them) that I just wanted to look and was certainly not buying. That same happy, generous, outgoing personality remains at the shop (whatever the face that's there that day), and I've personally watched many a new diver-to-be as their questions were answered and their appetites were whetted by amazing stories of the underwater world.
I've never felt as if I were imposing on anyone's time at my shop, but I've certainly felt that at some others. If I were to be calling one of those others my home shop, I wouldn't hesistate in the least to switch when a friendly shop would present itself.
When I'm away diving, I'll drop in on shops just because they're there. If they're friendly and outgoing, I'll usually add them to my list of stops, as I always seem to need a widget or two. If they're uncomfortable (or judgemental, even, considering I'm not a recreational clone), I'll never darken their door again (I can do without a widget until I get to the next shop).
