Tom:
why doesn't busking count?
It does - but it's peripheral and always has been.

where did the songs everyone sang in so many variations come from?
From people gathering together as part of their daily routine and singing.

did a landlord never pay a farthing to entice the better singer to his pub?
I don't know, but nobody has produced any evidence that he did.

Dave:
even the redoubtable Mr G was indeed a folky!
According to you everyone is a folky.

Are you really trying to say that no performers were paid to sing for over 2.5K yesrs?
I'm asking for evidence that the payment of money/goods (pre-1850) in a folk setting was anything other than peripheral.

I'm off to the folk club then and would like to tell the audience something else exciting
Tell them "Things in 1723 were not that dissimilar to now". You'll have them rolling in the aisles.

Don:
I don't believe you're qualified to say what I do and do not know
That works both ways. No academician would interpret my comments to mean that "ballads that spontaneous composed themselves". Or perhaps you could point out where I said that? (BTW it's 'spontaneously'). No academician would dismiss so cursorily eyewitness evidence that rural folk would gather at work and play and just SING. And no academician would resort to petty points-scoring and name-calling just because someone's opinions don't happen to gel with their own.

Charlotte:
I've heard far better music being played by the so-called "peripherals" than I've heard in many a folk club
Me too.