Well, there's a specific example that I think we're all keeping in mind here, and that account receives most of it's rewards from upvotes from one account. It'd be easy to simply spread those votes across accounts, eliminating that drawback (in this instance).

An additional benefit that might have prevented a great deal of controversy regarding that account to having multiple accounts instead of simply pouring all those rewards into one wallet would have been the obscurity that would have provided.