This is an example in everyday life of the application of standards. I further assume that this is a standard for the crews that paint those lines. There are reasons for standards. It has to do with people’s capabilities, with their ability to perform and to learn.
Matsuoka Roshi often said that the Zen person has no difficulty following the sidewalks. What he meant by that, I think, is that conformance to trivial aspects of society are not really worth the trouble to resist. And if we are bogged down in that level of non-conformity, we will not have the time, energy, or awareness to avoid conforming in much more restricting or damaging ways.