I think you need to take into account peoples regular ride/commute areas to assess their views correctly. I've only ridden in London 4/5 times yet have seen more poor/dangerous cycling in that time than all of the rest of my riding put together. This seems to be a combination of sheer volume and the faster paced, head down, me only, city attitude.
When we were cycling through Andover late the other Saturday I also noticed a few kids out on bikes. I saw 3 pairs where one was cycling and the other sat on the handlebars. This was all late in the evening, in estate areas and the kids were past, my view of, bedtimes, let alone playing outside time.
One of the problems is that, despite the vast majority that I see cycling properly, the dodgy ones are the ones you remember. The same as drivers, I can get home and all memories of the courtesy shown to me are wiped out by the one moron that tried to polish the side of his car with my elbow.