It may be about lack of education for some, but to make that a blanket statement is pretty demeaning to people in general. I do agree it probably factors more into the ammy decisions, but since the huge, vast majority of horse owners ARE ammies, it does pay to pay attention to that for many breeders (which is why many SO’s now make a point to say their stallion is EE). Ammies are usually looking to buy, or to breed, for themselves to have fun and possibly even show. Showing and getting to the top is not always the goal, and is often not the goal. So when you can be choosy, why NOT get the color you want?
Most people want a certain color car - it’s a preference, not ignorance, the car still runs the same.
Do you know how many sporthorse breeders/buyers absolutely stay away from spots? THAT is far more ignorant in most cases because of the stigma of “if it’s got spots, it must be from Paint blood and that just won’t do”.
I know one breeder who adores chestnuts, but will not REMOTELY consider any pinto WB stallion, no matter the quality. It’s not about resale value for her, it’s because she does not like spots.
It’s no different from people who want nothing but a plain bay, no chrome. Not uneducated. Personal preference.