Occasionally you get a comment from a car driver that (even though it doesn't even occur to them) highlights the fact they're ignorant of the rules of the road.
I cycled circa 5 miles to get a haircut (it was winter so I didn't get sweaty).
While sitting there, the girl was chatting and asked how far i'd come...
'5 miles...'
'Ooer, which way did you come...' (by starship ? perhaps she was thinking

)
'Down the parkway' (dual carriageway)
She looked shocked and said...
'But you're not allowed to'
'Eh, why's that ?'
'It motorway. you're not allowed on the motorway'
'Its dual carriageway, not motorway'
There then followed a 5 minute convo on the dangers of cycling, do I wear a hemet etc etc.
She was concerned, not judgemental, she just couldn't conceive of riding a bike probably, let alone on a busy road (which wasn't busy when I went there)...