They don't really give a hoot about the happiness of the animals in the stores!! Well, most stores don't.
For example, you can't house brown anoles with green anoles, or either species with geckos, but our LPS has all three species in one TINY cage, that's HALF the size of my 10 gallon!!
The tarantula's need at least a ten gallon, they aren't even in a 5!! I have a KK bigger than their cages!! My tarantula is in a leaky 30 gallon that we made.
That's a lot fro a fish!! Of course, Whip cost me about $6, but this was a rare occasion where I'll spend more than a couple of dollars on purchasing a fish.