Re: This should be one of the easiest taxes to collect ...
"Unlike the USA, pedestrians ALWAYS have right of way on UK roads except where expressly prohibited (motorways, etc)"
Although that's true most of the time, wandering randomly through moving traffic probably isn't a good idea, especially when drunk or just being stupid and running out into a road, and that will be taken into account.
Likewise, obstructing the highway is an offence punishable by a fine. You could argue that a pedestrian running out into the road without warning doesn't have right of way but is causing an obstruction. Pedestrians, and I one too, as well as a driver!) might legally have the right of way, but they also have a duty of care to themselves and others.