I know what you mean Gedi... Been there myself. I guess where we may differ is that I prefer to let market dynamics do their work, i.e. allow such clubs to close, if they cannot be run properly or in a manner that is still attractive to paying punters. But lack of standards does not tie the organiser's hands; they can still ask someone not to sing any more, and it is fine to say "because I don't like what you do", or "because the others don't like what you do", or "because I don't think your material/performance/face is right for this club". No need for "standards" to hide behind.

And I have seen "standards" being used precisely for that reason (i.t. to hide behind) too often. In my early days I had several rejections based on the "we don't book songwriters" pseudo-standard, when the club's website boasted at least three such in that year. And I was of course miffed at that lame excuse. It would have been braver but ultimately kinder to have said "we don't know you from Adam", or "I like what you do but you are not well known enough to bring in bums on seats", or even "sorry, I listened to your demo and don't like your stuff". No need to lie, no need to hide.

Organisers can exercise personal judgement, and then stand by it. They don't need standards to help them. The best ones will thrive, and the weak ones will die out over time. The market (and Darwin) speaks.