Gervase, your belittling remark about "anyone in Eltham" is quite inapt. As I said, anyone who has folked in London over the last 20 years and probably more should have known of "FolkMob". It was the home venue of the late Dave Bryant of this forum, and it was the place of the wake/collection for Brixton Bert. It was in every edition of "Folk London".

The - indeed your - cavalier attitude to that name and goodwill tells us much to your discredit.

It is not merely that "it can be called anything on the day". You should not have called it that at all. You appeared to trade (intentionally or not) on the goodwill of the FolkMob folk club. That is the essence of the tort of passing off, or what USAians would call common law trademark infringement (if they didn't call it passing off or palming off).