There's this story, I don't know if it's true, of a business who used to sell gay sex toys (I don't know what is specifically 'gay' about it, let's gloss over this for the sake of the story) from the back of magazine covers. Except they didn't have any inventory or anything - their entire business was to collect payments, guaranteeing 'discrete packaging' etc in the ads; but then call the customer and tell them 'we're out of stock, but we can send you a letter with our logo on it, and when you fill in the form in that letter, we'll send you a cheque from Gay Sex Toys Inc made out to you to reimburse you'. Their business floated on people who didn't want those letters or didn't want to hand in that kind of cheques to their local banks and who just left it at that.