Horsemeat is not part of the American diet. It would be difficult for people to eat horse, even if they wished to, as horse are not legally slaughtered in the USA for human consumption. I'm quite surprised.
Just around the corner from my home in Stockholm is a restaurant specializing in horsemeat; we go there often (great french fries). Perhaps my first taste of horse was 30 years ago in Japan, eating 'sakura niku' or raw horsemeat - basashi 馬刺し. Tasty! The odd thing of that neighborhood was its big horse racing track, and we regularly joked we ate the slow ones. Disappointed gamblers perhaps enjoyed revenge when ordering that dish.
I've surely eaten many odd foods over the years. Jellyfish in Chinese food is one. All creatures great & small, but I'd forgotten horse was odd.