You bet they will. And quick. More power to them.
Horsemeat is a traditional American food. County, city and later federal inspectors certified horsemeat supplies and suppliers for as long as there have been such inspectors. Dogs and cats are not traditional.
I've eaten back in the 70's when beef went sky high in price. It was in the grocery stores back then.
I can attest that at a Pro Ranch market in Phx there were things that certainly looked like horses' heads to me..that was probably four years ago. The meat cases there went on forever.