I agree with GUEST Andy above about having to sit through the same darned regulars before reaching the guest artist. Sometimes instead of. Our local folk club has singers nights when the regulars sing and then on guest nights the regulars do support (not floor spots you understand but support) for the guests. These tend to be people who never made it in the folk scene up to now and are hanging on for their break which they hope will surely come in their 40s and 50s, still waiting to be "discovered". Quite sad really. You would not pay a going concert rate to hear them. If a club charges a concert rate (£10+ a ticket) for a good artist I suspect the audience would be rather thin if they are expected to sit in a dingy back room and plough through darned regulars for 40 minutes of the booked artist.

At festivals you can choose a concert packed with good artists of various types or you can go to the singaround/session. It's not expected to be a mixture of both. And folk clubs hide themselves away in dingy back rooms and are spoken of as mystery and intrigue by the pub regulars.