The real benefit is that a more casual and honest environment is created at the conference.

At the typical sterile, corporate, business casual conference in my field (finance), there is a particular very boring code of behavior. There will be very little honesty - if you think a product sucks, or you think the industry is broken, you'll keep it to yourself. The guy from Morgan Stanley will never ever disagree with John Mack .

From LessConf's advertisements, I get the impression that their conference is more honest and more fun. The guy from Google might even disagree with Larry Page.

If this results in a few oversensitive people staying home, that sounds like a tradeoff well worth making.