I know this territory has been crossed on Mudcat a thousand times before. It's not necessarily a matter of "better", but just being aware of what you want to sing/play/hear. And the semantics of this are really quite important. I've been to folk clubs where I've heard primarily music that I consider folk. I've been to other folk clubs where I've had pretty much a whole evening of 60s and 70s pop songs performed by "man with acoustic guitar". I enjoy the former and don't particularly enjoy the latter. Nor have I particularly enjoyed most of the singer-songwriters (again, usually "man with guitar") I've seen (with the exception of gems like Tony Carling).

It's the ambiguity of what a "folk club" is these days that is the issue. It's easy to say that we should have a completely laissez-faire attitude and let people play what they want (which actually works in the folk clubs that I attend regularly, but is not necessarily a model), but people do go to events with expectations. I'm sure that almost anyone going to a folk club who was provided with an evening of electronica, e.g., would feel disappointed. It's not about value judgements; it's about expectations, and ultimately, people just listening to what they want to listen to.