Man, grow up!Stop encouraging this.
The reality is, a half gallon is a better fate than what a lot of these bettas in chain stores will have. A lot of these bettas will die in their cups at the store, and a lot will end up in glass bowls about the same size as the plastic cup they were sold in. Sure you can try to educate people but the reality is to the majority of people out there, fish are just mindless, disposable pets.
And if you want to go the route of "holier than thou", you should know that there are people who feel that keeping any creatures in cages is heinous.....................even if a single neon tetra was housed in a 500gal tank.