In order to understand this peeve of mine I need to give an idea of the lie of the land.
I attend a church on Sunday mornings (yes yes I am a hypocrite, but bear with me).
The church is about 15 minutes away by car in a 25 mph zone. On my route I pass one other church. Neither my church nor the one I pass has a carpark. The area is completely built up and the churches were built before cars were abundant. My congregation and the other church's congregation between them take up about half a mile for (completely legal) parking on both sides of the street.
Parallel to this churchy street are side streets to both east and west. The town is laid out in a grid so all east-west streets are parallel and all north-south streets are parallel. There are some streets that are clearly main streets and some that are clearly side streets, with some of the main streets busier than others because of shops, etc. The churches are located on a main street that is a bit less busy than those that have shops. It is mainly residential. People use it because it has a bridge over a major feature that divides the town, and that makes it a de facto main street along with the other main streets.
Anyhoo, on Sunday mornings the congregation parking on both sides makes for very narrow driving lanes. Two cars can squeeze past each other without knocking mirrors off parked cars if they are careful and drive slowly. Looking at you and still can't believe you thought I was wrong to screech at you that time, DD2
On fine summer Sundays whole families take to the streets on their bikes here - adults, older children and kids who are two weeks off training wheels all out enjoying the fresh air. Local groups of bike enthusiasts set out in their spandex and goggles and helmets. Parents of young children hitch big yellow trailers to their bikes, with little red flags hoisted aloft that are supposed to warn you to drive carefully.
Then all these people set off on a Sunday morning on the street with the churches.
They could easily use the side streets. The side streets would be much safer for small children swerving as they get into their stride, and for the parents with the yellow trailers, and far more suitable for the serious velocipedists who insist on riding three abreast 
. They could use side streets on either side of the very narrow church street and easily turn and traverse one city block width to get to the bridge. (This is how my DCs all went to the local pool on their bikes when the pool was the place to be all summer.)
They could just do their bike riding on Saturdays.
But no, they ignore the side streets and prefer to dice with death on Sunday mornings.