If you've kept bettas and watched them get stuck you'd know how hard
they
try to get air. If there's even a tiny opening in the water surface
they'll find and use it. You might be surpeise how strong they are.

I've kept many bettas but never in a situation where they had to fight
to breathe. This is no way to treat a live animal. You are suggesting a
situation that is likely to create stress and health problems.

They have found in depressions as small as heel-prints in the mud.
(Brown's account in a recent TFH)

Please post a link or more information where I can find this, because
the old Betta in a hoof print is so commonly used by people arguing for
smaller tanks that is has practically become an Urban Fish Legend. I
suspect one guy found a Betta in a hoof print, posted his findings on
the internet and the rest was history.

When there are so many options for appropriate Betta homes should we
really be encouraging people to buy these vases? It's up to the
experienced aquarists to teach new hobbyists how to provide for their
pets. The whole set-up trivializes the painstaking work aquarists go
through to maintain a system as close to what nature provides as
possible. It sends the wrong message and worse, unnecessarily exposes
the fish to a life of stress and disease.

These vases are widely rejected by aquarists and deemed as inhumane.
They have been pulled off the shelves of major retailers all over the
U.S. (maybe world, I have no idea) and much of it has to do with the
influence of experienced hobbyists and possibly the petitions that have
been circulating for quite some time. I haven't even seen a vase since
2001 myself. (until this post, though I'm not surprised they still
exist) As long as there are people to buy them, there will be some that
will sell them. Anyone wanting to convince the masses that they are now
safe definitely has their work cut out for them.