People can like whoever they want to like. Some people may only like those of a certain height, weight, race, class, and any other attribute you may want to think of, but it is not necessarily wrong. It is up to each individual to have the freedom to date whoever they wish.
You might be conflating this with the societal denigration of certain races or classes, which is surely bad because there really is no reason to denigrate them, but that is not the same as saying everyone must be attracted to those of any combination of the above such factors.