As I see it, the fundamental argument is whether cycling is a form of transportation, or a form of recreation.
Race cars are expected to use a track. Pedestrians are expected to use a sidewalk. Carpools have their own lanes and sometimes trucks do to. There are passing lanes on hills and slower vehicles should always stay right. All of these special rules are routinely violated by some.
The perception I think is that people riding cycles are "playing" while people driving cars are going somewhere. We cyclists aren't seen as having a destination or a real purpose for being on the road.
Cars on the road idly or just for sightseeing or being used instead of a sort walk to a destination aren't as easily distinguished from the vehicles which supposedly have a purpose. It is very easy I think, because of our distinct appearance for people to assume we are just "playing."
Do I have a solution? No. Not until there are more cyclists, many more, who are willing to use the road and vote for people who will take them seriously.
Carl
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Just Peddlin' Around