It seems kind of strange that the entire meat industry exists and is tolerated, yet a few horses in Central Park are making people so angry. Surely these horses have far better lives than the cows did that everyone's tucking into over lunch?

I do not know. I have not looked into this issue on the merits. I have just observed the gridlock and status-quo bias around it.

I suspect though that mandating better conditions would have the same effect --- the horse tourism business probably stops penciling out if they have to make the required changes. And given that, TWU would fight it just as hard --- a de jure or de facto ban has the same effect as far as they are concerned.

They've tried but the owners continuously don't.