I got both of mine from the LFS
in their little cup... each one now has his own 5 gallon he shares with 3 ghost shrimp. Their colors have gotten much brighter and their "attitudes" have really come into their own. They each have their own little quirks.
My blue/green/red one for example, every time I open the lid to go to feed him, as soon as he sees my fingers he jumps out of the water to try to get the food. He will eat right out of my hand as well. My red one just swims about halfway to the top, then waits for me to put the food in the water, and he "stalks" it... they are beautiful fish.
If I was a betting man, I would say even breeders keep betas in very small cups as the males just can't be put together, so it's easier for storage reasons than using a bigger aquarium for 1 fish.
I'd pick one up from the LFS
and make him a new home and give him a better life.