These actually don't bother me so much.

What bothers me is when I give an email at a store for receipt or refund purposes, and they take that as an opt-in to multiple marketing emails per week. And removing myself from the list often takes multiple attempts at "unsubscribe".

If I don't explicitly opt-in to marketing, I should never get marketing. Ahem, Microcenter.

Having proxy addresses is nice. But I can't just kill an alias if I'm using the email for refunds, or if I use the service multiple times. Also don't want to generate and read off alias emails when I'm at a cash register.