I'm not a huge fan of the unsolicited spam/letters/coupons/etc I get in my mail box from businesses and there's no way for me to opt out.
You can actually act on the advertisements and coupons, though. And the companies who sent those offers to you are obligated to abide by them. This potentially would be like if you got a BOGO coupon in the mail and when you tried to redeem it, they just pretended like it didn't exist.
FTR Some jurisdictions have laws where you can place a sign on your letterbox to prohibit that sort of spam from being placed in your mail.
This isn't even that - isn't it contacting people about using services they publicly offer?