In our industry, we really like social events and writing posts about social events. One of the latest Does Our Industry Have a Drinking Problem? poses the "as advertised" question. I'm not going to chime in with my answer, because this comment says it better than I could.
What I will chime in on is that on top of the blame being put on the wrong thing, the charge to fix it is put on the organizers of events instead of on the attendees. As an organizer, it is extremely hard to find somewhere to put 200-300 people at night after an event. As stated in the article, the de facto is bars not just because of alcohol, but because of the available space. Bars also function well because you can choose not to drink, but also be around the people that choose to. Unless you can arrange separate activities right next to each other, you are making people choose an activity and which groups of people they will have access to.
If you have read any of the articles about social events lately, it's very risky to hold one. It's more risky to hold one and have an after party. To imagine running one, running an after party and sending pockets of people off to where they would not be themselves is enough to drive them to drink. (Water of course). Personally, I have offered a section on my conf site for attendees to step up and offer up meetups. There have been a few each year: bar meetups, dinners, lunches, movie viewings, trips to the Dali Museum, jogs, etc. The key is allowing someone else to be in charge of it and others to follow that person.
What we need are leaders to step up at events. We need someone to say that they'd like to have a group do "this" surrounding an event and ask the organizer to promote it. In all of the problems that arise from social gatherings, we need to keep the focus on what we as individuals can do to make things better.