CNN article says Rome has banned round fish bowls, and says some article said they make fish go blind.

bowls

I am an aquarium nut. I'd have to see evidence on fish going blind in bowls to buy that story. However, it certainly is possible that these bowls, without any airstones or regular water changes, may become oxygen depleted, and a goldfish may outgrow them. But it doesn't say how big a bowl is big enough. Nor does it say anything about Bettas, which are often kept in the smallest containers.

The article also says the city banned giving away fish as prizes at carnivals. I'm in favor of this as I can't imagine more than 10% of those fish live longer than a week. Of course, baby fish don't have a high survival rate in the wild either, but it seems we should avoid causing suffering when we can, and being flushed in chlorinated water causes distress and then death. One of the worst lines in Nemo is the one about all drains leading to the sea, or something, possibly encouraging kids to believe they are freeing their pets if they flush them.

So, on the bowls, I'd say it depends on the nature of the fish, the size of the bowl and the maintenance practices (unless there truly is scientific proof that living in bowls causes blindness -- if that is the case I have to wonder about every aquarium [but I've never noticed a blind fish in any of mine]).

I've read that many fish in the hobby don't live very long. What I haven't read is how the percentage compares to those who grow up in the wild.

Anyway, interesting to think about.