It's all about personal preferences...
You're not for everyone, and not everyone is for you. That's as it SHOULD BE. I read and see a lot of things on the internet that I don't care for, also. Your curiosity is natural; on this particular site, there are many who indulge in, or fantasize about interracial sex. It's simply their 'thing.' There is a certain stimulence (for a myriad of reasons) about being sexually involved with someone of another racial background. It just is...
And, of course add the additional factor that it's an adult sex site, which means that just about everything you read has been embellished to make it fit the fantasy of the writer.
You seem to have already decided that you 'can never be with a black guy.' As a 'black guy,' I completely understand YOUR CHOICE. There are those who will ask why (simple answer--you choose NOT TO), and castigate you for your choice. Let that be THEIR problem. On the other side of the coin, there are those (black males and white females) who DO CHOOSE to have inter-racial sex. That is THEIR RIGHT, their choice. And that is perfectly fine, also.
I'm simply saying, 'live your life as you see fit, and respect others rights to live theirs as they see fit. You'll do just fine. No further analysis needed.