I've come to expect being added to marketing lists after having a transaction with any business. (That doesn't mean I like it though, and it's one additional hassle that keeps me from shopping at new enterprises.) I agree, if you make it easy to unsubscribe, no ill will.

What is most irritating is those businesses that I have already unsubscribed from, or clicked a box saying I didn't want to be contacted, who, months later, start a new list and make the default subscribers everyone who has ever had any business with the company. Saying I don't want to get your marketing emails doesn't mean I don't want them until you invent a new category of marketing; it means I don't want them ever.

It's a lack of respect and it pisses me off.