Yeah, I think we have totally opposite opinions on that! But I will say that zoos take animals that have been rescued from the circus, not the other way around.
Animals don't enjoy the thrill of performing, they do it out of fear of the cruel things the trainers do to them if they make a mistake.
And if they're not performing, they're in a cage they can hardly move around in. Granted, some zoos are almost as bad, but I don't support roadside zoos. Zoos do train smarter animals like elephants enough to keep them mentally stimulated, but they aren't forced to perform on cue if they aren't in the mood. Also most of the training they put them through is to aid in giving them medical examinations, like training elephants to lift up their feet one at a time to be inspected for sores.
Btw Ras, you really need to see Madagascar 3. It depicts the animals enjoying the "freedom" (yeah right) of circus life instead of being in a zoo. There's also a Russian tiger who's addicted to borscht.