Don't see the reason why would they do that, this is just another altcoin, doesn't have anything to do with Bitcoin. Anyway, I got the feeling that majority of exchangers, at least those bigest and most important ones, will not support BCC. Could be a lot of confunsions before and shortly after August 1 until everything gets back to normal.
It's not about exchanges supporting BCC it's about them not stealing the BCC from their users. Let's imagine that somehow it becomes a success and the exchange is left with millions/billions worth of BCC but never credited it to their customers. It would be outright theft.
In fact the more exchanges that credit people with BCC the less relevant it will become due to the impending dump that will follow.