Some people bought my game, and now I'd like to email them and offer them a discount on something else. Is this OK as long as I give them the option of opting out of any future emails? I didn't ask their permission to email them when they bought my game. Can I assume their purchase expresses an interest in future products?
I already know how I feel about this issue, but I'm wondering what the consensus is out there. If you bought something, would you be annoyed if the author offered you a discount on another product? Would you be pleased?