Nike knows if they make a pink sole charcoal reg retail shoe they won't sell well. And the CB line is not so popular that they can offer them on id. Plus Rafa and Fed probably got something on their contract they can pick any custom design shoe they want.
Only people on forums checking these threads would know the shoes are different. I bet 99% of the consumers out there don't even know or care for that matter. The stores tell them "this is the Federer shoe" and they would just buy them.