I also keep getting spam

I see that I am not the only person who keeps getting bombarded by spammers from this site.

Are you quite sure that these are human spammers? I haven't posted on here for quite a few weeks, I can't believe that someone would search all the way back until they found one of my posts. Why is it just this website that has the problem? I am a member of literally dozens of websites and I never get any spam from them.

These spammers are including websites in their messages, are they working on behalf of these websites? Surely a kosher website is not going to allow this kind of spamming on their behalf?