No controversy at all.. I also hate to see them up for adoption. I think however that is due to their relativity inexpensive Pet-Store price. They are cute little impulse buys for many people and when folks figure out they don't just go belly up like a Gold fish after a year or two or die in their sleep like the Pet hamster then pet loose interest and have to get rid of them..
Want to cut down on that if pet stores would stop selling them for 35.00 and ask 100.00 for one you'd see far less of that I'm sure.