Can anyone please tell me I've got it completely wrong and what Bryan and Co are doing is actually the norm on the folk club scene? Have I just been incredibly and consistently unlucky?

It's not something I came across when I lived in N Wales nor something I've heard of now I live near Cromer, Norfolk (and usually going to Norwich for music).

When it comes to looking for folk music (other than concerts), I think it can be useful to go to a couple of events you do find and asking around. I found an Irish session (the thing I hoped to find most of all) through going to the Norwich Folk Club. From that session, I learned of another Irish one, and then a couple of others, and now I know a number of people, could probably find much more to do than I know of if I wanted to,