Is It OK for Cars to Touch One Another?

Cars don't have the same uncontrollable flow as crowds. Maybe it's because cars are never considered acceptable for them to touch each other at all. People mostly avoid, try to avoid touching one another in crowds. But in some situations, maybe it just seems like there's no avoiding it, so you just sort of resign yourself to touching and then that can build up. I wonder if this stricter no touch policy with cars has some sort of influence on us.