To me, nothing says “I can’t cycle and I don’t care about cycling” more than those idiots who ride on sidewalks on seats that are too low for them on shiny hybrid or mountain bikes with earphones on and their U-lock hanging dangerously off their handlebars. Today one of them even had a U-lock hanging there that was not even locked — the straight end of the lock was swinging merrily from one attachment point to the curved end. I do wish their locks would get caught on something and throw them to the ground, like what happened with one bloke on the CCC Hegewisch tour (unsurprisingly, that bloke was also riding with a seat that was too low for him, on a mountain bike).
They can’t cycle — that’s why they’re avoiding the roads. They don’t care about cycling — that’s why they continue to break the law and give a bad name to all cyclists, and ride so sloppily.