Literary festivals

I haven't been to a literary festival, but apparently they're taking over from music festivals as the go-to event. Or so Maggie Womersley says in her blog here

I'd love to go to one, but I'm not so sure I'd find it all that thrilling. What do people get from going to these things? Now conventions, I understand. I understand the thrill of meeting other people who enjoy the things you do. But it's the variety of responses that excites me, the people who are into cosplay, into the collecting, into fanfiction, into talking about the ideas. The gamers, the crafters, the dreamers and the party-goers.

Will I have all that at a literary festival? After some of the conventions I've been to (and some of them have been truly spectacular) wont they just be a let-down? I'm thinking particularly of the Redemption convention, run by and for volunteers. The whole range of events from book launches (yes, those too), to morris dancing, lectures about science, debates and the good old Blake's 7 drinking game

We're engaged with the process, not lectured or sold to. We have a real stake in what goes on. How many literary festivals can say that?