Why do you cut out a coupon from a decades-old magazine, fill it out carefully, and send it in to me?

Do you think sending a coupon from 1962 will magically transport you back to that year, or that we still have vast piles of A Treasury of Great Science Fiction that we're not selling?

Do you not realize that we don't enroll everyone who tries to join, anyway, so it really is no trouble to just throw your coupon away?

What on earth do you expect is going to happen when you do this?

I've gotten a whole bunch of these in the past month or so, and I want to know if there's someone out there encouraging this strange behavior...

Update, fifteen minutes later: Of the five pieces of white mail I just opened, two were moldy old join-the-club coupons and one was an indignant "why didn't you enroll me from my moldy old coupon" letter. Again, what are these people thinking?