Ok, but my core question still stands: why? I'm with you in thinking that noreply addresses should go away, but I don't see how this could be an effective measu

Ok, but my core question still stands: why? I'm with you in thinking that noreply addresses should go away, but I don't see how this could be an effective measure to stopping them. A company isn't going to care about this, statistically speaking. Everything you're describing sounds tedious for no gain.