that same mentality reminds me of how religious people say, "men and women are created to be together" and believe homosexuals CHOOSE to be gay. Even though i completely don't believe this theory, it still makes more sense to me than saying that people are meant to stick to their own race. It's like god saying (before america came into existance), "don't leave your country - EVER. don't ever marry someone out of your community".
I think my history professor even once said that people become genetically stronger by mixing races (otherwise, that race tends to form certain weakness. Like, you ever notice how black people are more prone to certain diseases, as are whites and hispanic are prone to others?) The "stick to your community" mentality has been around since almost as early as humanity. At first this was useful for survival (a defense mechanism against other tribes/enemies) which is understandable. Offering a woman from your own tribe to another was sometimes a peace agreement. When people could only preserve legends verbally through generations, sticking to your "own kind" was also somewhat important. In my eyes, this mentality eventually became silly (writing was invented, and communities have grown) - parents simply wanted their children to preserve "tradition". I don't see what's so important about doing or believing the SAME EXACT things as generations before u; for me, nothing's set in stone.
Of course i respect your opinion and all, but sometimes i just don't understand people.... (but i am VERY glad you are open-minded enough to accept other people's choices; it's pointless to stress about what OTHER people do with their lives)