I strongly suspect that "Do not send me marketing emails" at checkout time ACTUALLY means "Wait 6 months before sending me marketing emails, when I might plausibly forget that I checked this box", because I always do my best to opt out of mailing lists and I always seem to start getting stuff anyway 6-12 months after making a purchase. The Silicon Valley model of consent strikes again.
They classify it as "transactional" emails (like what is supposed to be order receipts, shipping updates, etc) and so "decide" they can send you an "order update" to an "existing customer with a business relationship" 6 months later, instead of adding you to the spam list immediately.
I just received a marketing email from Dell, and in the footer they claimed it was a transactional message. The last transaction I made with them was 3 years ago!
It's insane - I rarely want marketing emails (there are some I do, new products from Saddleback Leather are always interesting) but when I do actually find out about some new product that's desirable, I find that I never get marketing emails for it, even if I'm signed up to things you would think would cover it!
Apple knows who I am, what I've bought, and I'm not unsubscribed from all, and yet they've never told me about the Neo, though they did send me an email talking about the event that might have been the one that revealed it.