Disclaimer: IANAL.

But I seem to recall there was something like this with book clubs, that they'd send you a piece of mail, and you had to reply to opt out. Otherwise they would start sending you books, and charging you for them.

That kind of garbage became illegal in the 1970s or thereabouts. I can't imagine that doing it via e-mail makes it any more legal.

The only leg that Apple has to stand on is that it's going to be really difficult (expensive) to sue them. I'm pretty sure that the actual law is not on their side here.