I'd like to take this opportunity to echo bgwah. Scapegoating/mocking vegetarians and vegans is a super-annoying tendency of liberals. They're an incredibly marginal political group. The "yuppies" you're talking about are overwhelmingly not vegetarians. Most of them are probably omnivores who are into locally-sourced, grass-fed meats, or whatever.
Sorry to be so reactive to this, since I know you probably didn't mean much SweedishCheese, but the "I'm not an animal rights nutcase!!" stuff from left-wingers on this forum gets pretty tiresome, and this thread is starting to head there.
I'll abstain from voting for now. I don't actually know anything about this industry or practice, and this thread hasn't been very illuminating.
You're probably right about the political clout of vegetarians/vegans. But, this is certainly an example of the political strength of animal rights activists within the Democratic primary in a liberal city. If we held a referendum, I think most people would want to keep the horses, but a passionate group of people were able to torpedo Christine Quinn and now they're getting what they want.
Also, I'll put myself in the same camp about admitting my general ignorance about horses. But, nobody here has even been able to articulate a reason for banning the carriages in Central Park. On top of that, the NYPD still has horses. Isn't it completely arbitrary to allow the NYPD to ride horses through the busiest, most congested areas of America in lower Manhattan, but say that the carriage ride horses should be banned? Isn't it arbitrary to allow the use of horses for racing and farm work, yet ban them for this one purpose?
We're also talking about the livelihoods for hundreds of people. Unless opponents can articulate a strong, non-arbitrary reason for banning the practice, it seems fair to allow the horses to stay.