Its a COUNCIL event, not a club one.
Seriously? Do you live in a cave?
Ask the council. I guess they want to avoid anything too out of control. Not that there would be anyway, but there you go
Why would there be any 'luzzing'? I'd imagine they just don't want to start the summer tourist...
I'd imagine that the council had a view on when it was possible / appropriate / acceptable to SHUT the busiest road in the city for 90 minutes. The reaction of all their business rate payers in the central shopping areas were probably high in their thinking, and reasonably so, IMO.