Shiels maintained hundreds of e-mail accounts that received the removal requests. Some spammers, he said, use the removal requests as proof that those addresses reach real people and increase the spam.

The point is that a response means, you have just confirmed your address. If someone sending spam actually collects these and removes you, there is no provision to prevent that same spammer from selling a List of Confirmed good email addresses. You provided the confirmation.

True, you should get anything from the same sender again. So one hour they are pam00000123456 and an hour later they are pam00000123457 and the spam continues.

There is software that picks up email addresses from sites. Your address will be sold if you regester software or sign up for some news services (just examples) There are also address generators that will write to bob1@sitename through bob100000 in sequence, and then move to joe, marie, suzy... you get the idea. Your real name can be found by accident.

My personal way of dealing with it, is delete and ignore. Fortunatly the new SBC Yahoo (formerly Prodigy) has BULK mail and spam guard. I hit delete and I don't even see it. What does sneak through can be deleted or reported, which means that sender gets blocked. It works!

I get spam on an email account, on another service, that has never been used to send anything but one lone email to one person, who I know is not a spammer. These search tools can find addresses that have never been used, but are active and not bouncing mail...

"Have you got anything that doesn't have spam in it?"