Great article and good points.
I did one a while ago about the various species of livestock that are dying out and going extinct because of big agriculture and mass production. If people stop raising their own heritage breeds, no one will, and we will forever lose many unique kinds of goats, pigs, horses, chickens and such. Different subject, but another way that something many people oppose (raising and eating animals) is actually beneficial for the species). - My point was, "If we don't eat them, they'll go extinct."

Likewise, many people may disapprove of zoos, but they certainly do serve a purpose and benefit animals. Great post!