Are certain personal preferences bias or prejudice or just a personal choice?

I have a friend that says that when he dates a woman that isn't a redhead that the date doesn't turn out very well. So, he's decided that from now on that he's only going to date redheads. I told him that his decision was bias and prejudice. He says it isn't that it's a personal choice. Who's right?|||Personal choice---silly--but he is entitled to make that decision.