Here's my take on it:
I have poured tons of my emotional baggage into Everything (see my personal hyacinth girl and related nodes), and I was duly rewarded. But I'm not talking about XP here. I don't really give a shit about that. What I did get was a few dozen sympathetic ears, and some suggestions about how to let go. And it felt really good to open up to all these people, secure in my semi-anonymity. It made me feel better. Emotional prostitution? Maybe. But not for votes, not for XP, just purely for the emotional release I got out of it.