Why are fish exempt?

As California slips into bankruptcy, the right honorable San Francisco Commission of Animal Control and Welfare (really) is considering a law that would ban the sale of pets.

San Francisco could soon have what is believed to be the country’s first ban on the sale of all pets except fish.

That includes dogs, cats, hamsters, mice, rats, chinchillas, guinea pigs, birds, snakes, lizards and nearly every other critter, or, as the commission calls them, companion animals.

“People buy small animals all the time as an impulse buy, don’t know what they’re getting into, and the animals end up at the shelter and often are euthanized,” said commission Chairwoman Sally Stephens. “That’s what we’d like to stop.”

San Francisco residents who want a pet would have to go to another city, adopt one from a shelter or rescue group, or find one through the classifieds.

I need to know, why are fish  exempt?  Is it because when you tire of a fish, you just flush it?

The commission plans to listen to testimony from pet store owners, among others, before voting. Among the items it will consider is the impact on small businesses, whether to allow the sale of feeder rodents for snakes and other reptiles, the sale of fish, owner education, penalties and rescue groups that host adoptions at pet stores.