I've seen a variety of approaches used (I'm not usually the one doing the confronting) but I still haven't seen any shame, etc. Which is weird, because it's not like it's one monolithic group? But it's still what I've seen.

It might be that people have their change of heart more privately, of course.

What are you expecting? Someone to go on the Internet and apologize or otherwise express their genuine shame and desire to change?