I went to one in Cancun years ago. No doubt it's inhumane, but that could be said about a lot of things - cooping chickens for eggs, slaughter houses in general, hunting. Different culture, different mindset. An associate of mine was in China the week before last and said that he saw dog on a restauarant menu. The woman who was with me in Cancun said the bulls were born to die so she wasn't upset about it, but she was on acid at the time and also enjoyed skinny skiing.
Okay, the last part is from Caddyshack, but the rest is true.