I mentioned that it was possible to set up filters on incoming postal mail. I haven’t done this yet, but apparently the way to do this is via USPS DMM 508 §8.1.1, which says that “an addressee who receives a solicited or unsolicited advertisement offering for sale matter that, in the addressee’s sole discretion, is ‘erotically arousing or sexually provocative,’ may, by completing Form 1500, obtain a prohibitory order directing the mailer of the advertisement to refrain from making further mailings to that addressee.”
The key is that it’s “in the addressee’s sole discretion”. So if you claim that those credit card offers are just too arousing, the Post Office won’t disagree with you. Apparently, the Supreme Court has upheld that this even includes a “dry goods catalog” if the addressee wants (although I haven’t independently verified the existence of the court case referenced on that site).
I just find this an amusing approach to the problem. I may try it out sometime and report how it goes.