I have idea that also buildings like curiosities could call which stops are in coverage.
At this time only factories call it - and I think that also other special buildings (like curiosities and monuments) would call stops in coverage.
May it be that in case of curiosities and monuments it is not so important like in case of factories, but it would be helpful too also in this case.
As far as I know, factories are more than simple buildings, whereas curiosities and monuments are just that (once created, in terms of data structures). So if they get information about stops in coverage, every building gets them. That may or may not be a bad idea, depending on how costly it is.