The council don't have discretion in situations like this, unfortunately, Folkiedave, cos they are merely administrating proper statutory law

Nonsense. They have discretion to prosecute or not. In Sheffield the Lady Mayor danced to amplified music in the Town Centre. The council called it all (ballroom/reggae/hip-hop etc) morris dancing and dancing of a similar nature to get around the law. When I pointed out that it was still illegal (amplified music) they shrugged their shoulders. They would have had problems prosecuting anyone else for the same offence - and they haven't. Eventually they licenced the whole of the city centre. It is down to an individual council's interpretation of the law.