With the exception of putting the male bettas together, what is the big deal, really? They are meant to sell quickly and I know, in the stores around me anyway, they generally do. They get their shipments on Tuesdays and usually by Friday they are just about out of everything or very low anyway. I know that when I kept angels, their shipments would come in on Tuesday, i could go in there on Wednesday and there would not be a single angel left until the following week. The same thing with their oscars, fancy goldfish, and fancy guppies.
I don't mean to sound rude and I understand where everyone is coming from, but they are pet stores and they can't follow the 1" to 1 gallon rule. They simply don't have to room.