I've been to a lot of GCs in many states, and I've not encountered very much condescension. Maybe it's just how I act around the salesguys; I dunno.
Generally, the most annoying GC employees are the ones who are clearly in a band (or a lot of bands) themselves, especially if they're middle-aged and Never Made It Big. The guys who insist on playing the instruments themselves as a sales technique.
Lol! You described my local GC!!
Unfortunately “Mr. Slap-Happy” may have moved to my favorite local Mom & Pop music store.