It was always accepted in folk clubs that people were there to listen. It was also accepted that anyone was entitled - depending on time constraints, of course - to a floor spot, and everyone was given the courtesy of silence, whether amateur or professional. The standard WAS irrelevant. If you didn't like a particular floor singer, you could always head for the bar. You'd only lose a few minutes. As regards the value-for-money question, in those days, there was normally a resident group/singer, who was usually either pro or more often semi-pro. So they were able to maintain a certain standard, so that even if one or two floor spots were a bit iffy, the audience still felt that they had had their money's worth during the course of the evening. Compared with, for instance, the cinema, a folk club always was pretty good value for money. If the resident group wasn't up to the mark, however, the punters would find a better club, and the dodgy one wouln't last very long. Thus natural selection maintained the general standard.
Somebody back there said they blamed TV. Not sure whether this was meant to be serious or not, but in fact it has some relevance. Because people are used to entertainment via TV, video and now t'internet, some of them have lost track of how live entertainment works: that you've got real people actually performing in the room, to a real audience. And that if you talk, it can really be heard by the performers and the audience, and is distracting and ill-mannered.
John Kelly.