I would be surprised if I've met anyone in the US who has eaten pig ear nor the chicken feet you see next to them in the hispanic market. And just about everyone would react to the ick factor.

I don't think it's as common as you think: https://en.wikipedia.org/wiki/Pig%27s_ear_(food).

I don't really know of anyone who eats pig ears but chicken feet aren't that weird for the American South.

It's not super-common but it's nothing out of the ordinary either. Many restaurants in Southern Europe, including France, serve dishes such as pig feet, pig snout or pig head.