Oh of course not. Its absolutely terrible how bettas are so often treated like they're not even living creatures, its disgusting and not at all fair. I was definitely very happy to hear that the teenagers had been kicked out of the store, and the reaction of the several employees who I did show this guy too as I got my plants definitely showed that the employees do care. My Petsmart is pretty alright, the cups are usually decently clean and the bettas are generally fairly healthy.
I am a little surprised they didn't notice them sooner, I mean I spotted the two in the cup almost right away....but I suppose it just is one of those universal sign things; I was meant to find them and take this little guy home. xD
Based on quite a bit of personal experience, I am very of the option that any animal chooses you. All of my dogs choose me/my family, my horse choose me, my Leo choose me....and each one of my fish choose me; I've never brought a betta home that didn't give me 'the eyes'. ;)