No animal should be housed in such a way that aesthetics and space limitations come first.
Yes, a betta could possibly survive in such a bowl, but for how long? Would you lock a horse in a stable for it's entire life, never able to come out for exercise or to play? Why do it to a fish? Is it because some 'stat' says that a betta can survive in that small space? Because you see them housed in a tiny vase temporarily in a shop and think that makes it OK? Because they're not cute and fluffy, and you can't hear them scream when they are suffering?
When providing a home for a living being you take on the responsibility for the health and happiness of another creature. Why should a creature be forced to just exist? Do they not deserve space to swim, room to explore, things to do?
When providing a home for a living being we should consider what they need and would want, not what we can fit/afford/like the look of. If we can't do them justice, we should not take the animal on at all.
These could be used for loads of other cool things - why advertise them as a home for a living being, when they would be no better than a cell for them?