It definitely depends on the individual store and the people that are staffed there. Some stores have a wonderful, caring staff, and some do not. I go to Petco (far too often, in fact), but mostly out of convenience. It is a whopping 30 seconds from my house. My Petco does a good job with their animals, the aquariums are always spotless, the bettas are kept pretty clean (though they tend to be overstocked, IMO) and the small pets' enclosures are clean, as well. I'd never buy a small pet from any pet store (I adopted Bernadette, my old lady rat from Petco, after her family left her there), but my first 2 bettas are from Petco. My second boy has an injury/congenital defect on his face, leaving him blind in one eye, and I probably could have gotten him for free if I had complained about it, but I didn't mind paying to take him home; he's a wonderful little animal.
I would suggest going and inspecting - thoroughly - both stores and see which one is kept cleaner and staffed better.
The only cure for ignorance is education, and bullying or attacking someone is no way to educate them.