The personal is technical
On the day the translation was a mixed success. Unlike most Meetups, which can work with any number of attendees, a job fair requires a goodly number of recruiters, and recruiters will only turn up if they think there will enough candidates to make it worth their while. This first event didn't achieve that critical mass, and I would be quite surprised if I get an opportunity from it. Nevertheless I will try to attend the next event, whenever that may be, because pop-up job fairs in bars are a great idea. Not for the reason you're thinking (I drank cola all evening), but because it was enjoyable. I talked with some interesting people, and got a couple of email addresses as well.
But more than that I was impressed with the concept. The informal social setting is good for understanding what a person is really like, specifically what they might be like to work with. This has to be worthwhile. The CV is a dead letter: it lists skills and accomplishments but doesn't animate or demonstrate them. The formality of the technical interview makes it hard to judge somebody as a person. Anyway it's generally aimed at establishing how much of their CV is true. The social element is often missed entirely. Big mistake. Software is like Soylent Green, it's made of people.
Personality matters: the toughest problems most projects face are political (organizational, personal) rather than technical (except for system integration - that's always going to be the biggest pain in the neck). A modern development project is a complex set of relationships. There are external relationships, with users, with senior managers, with other stakeholders (Security, Enterprise Architecture, etc) any of which can jeopardize the success of the project if handled badly. But the internal relationships - between Project Manager and staff, between developers and testers, or developers and DBAs - are just as fraught with difficulty.
The personal is technical because the team dynamic is a crucial indicator of the likely success of the project. You don't just need technical competence, you need individuals who communicate well and share a common vision; people who are (dread phrase) team players. That's why Project Managers generally like to work with people they already know, because they already know they can work with them.
For a new hire, nobody knows the answer to the burning question, "Can I stand to be in this person's company eight hours a day, five days a week, for the duration of the project?" Hence the value of chatting about work and other things in a bar on a hot summer's eve over a glass of something with ice. I'm not sure how well the model would works for recruitment agents, but I think it would suit both hirers and hirees. It's not a technique that scales, but if people made better hiring decisions perhaps that wouldn't matter?