Ok, wait a minute people, I agree the store could probably put their fish in bowls, but remember that bettas are surface breathers, and so don't require a lot of airation, and as long as they are changing the water, which they may or may not be doing if they are in bags...but in any case, you can tell if the water is getting gross with bettas if they develop kinda a slimy scale on the surface. (it's really nasty you can't miss it.) At least that's what happened to my poor dorm betta when I didn't clean his tank every week. I only had him in a one gallon (and I was being generous!) and he was perfectly happy, I even had a little stump in there for him to hide him, too bad a friend of mine killed him, I miss Howie. ANYWAYS, my point is they don't need extra aeration and you have to remember they're really hardy! Just take a closer look at the fish before you jump to anything. You know classic signs of disease, or stress (lighter coloration, or spots from rubbing against the bags...)