Re: Celtic Connections. Never made it there myself so I'm no authority - but it is generally understood and recognized to be a unique festival in its format. It is a series of small concerts, and most people go to them to listen to music. Maybe it is a North American thing, but if I did go, it would be with that intention. And after a few hours of that, after the concert(s) wrapped up for the night, I might head to a bar to see who I'd run into, and yuck it up with some old friends I hadn't seen in years ...

I'm not really a big attender of folk festivals in general, to be honest. But what I've seen on this side of the water is, typically, a number of small outdoor stages and a main stage on which there are PERFORMANCES - the audience watches and listens, laughs, sometimes a few people dance informally - any "participation" beyond that usually depends on whether the performer asks the audience to participate in some way. Sometimes there are "workshops" in which participants are welcome to participate. Sessions as such are peripheral, hit and miss, and, in Canada at least, I don't think you'll find much in the way of "sing-arounds". Unless I'm hopelessly out of date. Which is possible.

Cape Breton has an exceedingly rich musical culture, and music is available there in many contexts year-round; some of those contexts can be very boisterous and participatory, but when people go to concerts there, they go to listen.