I wouldn't eat horse for the same reason that I wouldn't eat beef (read: I'm a vegetarian!) but if I ate meat, I think I might be prepared to eat horse.
Just so. I'm a vegetarian too, but I think that once you've decided that it's OK to kill animals and eat them, choosing which animals to eat is simply a matter of local taboos. As everybody knows, my ancestral culture has more... adventurous eating habits than many, especially in the south.
Horse-meat is eaten without qualms in East Asia wherever is is readily available. It is something of a staple in Mongolia and other parts of Central Asia, where nothing derived from horses goes to waste (fermented mare's milk wine, yum!

), and donkey-meat buns are a Beijing regional favourite. Australians don't generally eat horse-meat (a few "gourmets" feel they should, in emulation of the French

), but horses
are slaughtered for meat here, and each year thousands of tonnes are exported to Japan, Korea, and China.