I would edit your observation as follows:
The first example includes the unlikely possibility that Bill might mash fruit into his hair, and makes clear that he doesn't do this.The reason I make this edit is that in the absence of any context that would make Bill's mashing fruit in his hair a plausible possibility, I believe it would be unreasonable to even consider that Bill might mash fruit into his hair. Therefore, n the absence of an appropriate context, I find the two examples convey the same message.