> if you had someone's email you could be sure the message directly reaches him

You don’t get it. I don’t want your message to directly reach me. I want you to kindly f-off and don’t waste my time with endless offers of shit that I don’t need. You think your message is worth it? Pay me for my time to look at it then. I think it is a great idea. I wish someone did it for phones as well. “p2t2p won’t answer your call as you’re not in the list of approved callers. Press hash sign to make a paid call for a small fee of 1 AUD a minute if you really think your phone call is worth it."