We used to say about JSConf EU that it is five days of parties with a conference in between. We started making significant changes to that model five years ago and this thread sums up nicely all the reasons why.

Did you ban alcohol completely, or just try to make sure there is no expectation that people drink?

We stopped emphasising the drinking and focussed on people interaction. We have a wide variety of great drinks available for free, only some of which have alc (light beers), but the majority doesn't. Hard liquor is only available mixed and not free.