How can Party SNGs be long-term profitable?

[Lloyd]

This is a serious question. I think I play quite well. I've certainly won my fair share of MTTs, no-limit ring games, and have probably won more than I've lost in 1-table SNGs. But I just can't believe that 1-table SNGs (at least on Party) are anything more than luck. Pretty much every game comes down to 7 or 8 people with huge blinds and everyone shortstacked. So whoever gets lucky and doubles up usually finishes in the money.

I guess there is some skill in selecting what hands to go all-in with. But what else am I missing? I've read a lot here about people earning long-term profits playing 1-table SNGs. Where else does skill come into play? How can they be profitable?