Well, the native Indians ate them all and actually had none until the evil white man brought them back over.
I guess for the same reason we don’t eat dog, both are man’s best friend.
Mostly I would say that the horse has been more romanticized film and TV than the cow or pig.
Horses have certainly been made pets more than cows or pigs.
Also up until the mid 20th century the horse was much more valuable than the cow or pig because of the need for its ability to pull wagons and plows.
The French do eat horse but I believe that it is a more expensive meat. There is no health reason that I know of related to eating horse meat so really do not see the need for all of the fuss except for the meat not being as advertized.
What about the ‘NON-native Indians’?...........;^)
“I guess for the same reason we don’t eat dog, both are man’s best friend.”
Dog is an Okinawan delicacy.