i posted in a separate discussion, so I'm just going to copy and paste. Unfortunately, I don't feel like adapting it solely to your question, no offense.
From someone who attends an HBCU, you have the rest of your lives to be around white ppl. As mentioned before, at certain schools, particularly the private ones, there is the oppurtunity to interact with students of different backgrounds. All black people are not the same, so of course there is some form of diversity on an HBCU campus. At private schools inparticular, you have different economic and social classes, as well as people from all of the united states, and some from African countries as well. This is not something I read in a book or saw on tv, the right HBCU will prepare you not only for the real world, but prepare you as an African American in the real world. True there are some down sides, like not having hot water for a few days and long financial aid lines (that's why you get scholarships and you don't have to stand in those lines), but the HBCU is an experience that every African American should have. The friends and the connections you make, in addition to the memories from an HBCU are priceless. Eventually, you can look back on the bad times and laugh.