Direct mail by postal service does not cost the recipient. To receive CompuServe e-mail costs the user, especially those who have to dial in long distance. The same is true for most Internet e-mail. One way or another, charges are time-based. Those are the key words.
Time is money.
Throw away your postal mail - Hit delete on your computer. I would argue that the time it takes someone to unsubscribe is less than the time it takes somebody to throw away all of their junk postal mail that they CAN'T unsubscribe from. I don't think we are talking about apples and oranges. FYI, I did not even bring the compuserve information to debate this. I am not convinced that they are infact talking about postal mail in the first place.