I'm not sure that I understand the question, but what predjudice is as you say reinforce a stereotype that one type of person is better than another.
If you take your cow question a man with 3 cows may be superior than a man with one, but this cannot be proved because he has more cows. The assumption that he is, is all thats wrong with predjudice. The no cow man may be in every way superior.
Then there is the the fact that this assumption is then used to to "reward" 3 cow man when he may be entirely undeserving of reward.
You cannot make any assumption about anyone based on a stereotype.
Nature has been quiet fair in this respect nice people come in all colours, religions, creeds, shapes, sizes and intellects. Unfortunateley so do a$"eholes