You meet them in the hallways outside the talks.

Yeah, pretty much. At this one particular conference there were actually loads of stands in the hallway and I would hang out and chat with various people there.

The more professionally organised ones don't tend to have that many stands, except for paying sponsors. I understand why they do that, but I think there's good value in "community stands" too.

I mean, the talks themselves are just "shut up and listen", right? Not too much socializing happening there. I think that revolving the entire conference around presentations is probably not always the best format.

At the conferences I went to it looked like most (80%) shuffled from one talk to another. The hallways were for walking to different talks. You could potentially talk in the queue to get in or out of a talk but no one talked to me at all.

There was a big space for vendors to have stalls but if you talked to them it was like talking to a sales person. Sometimes they had a tech-oriented sales person but it was still selling you their product.