[giantg2]

I image it would be hard do transit maps if you weren't connected to get the schedule.

[Scoundreller]

They already get them somehow while "online". Offline with beginning & end times and a rough idea of frequency should be good enough for local use.

Offline road maps are subject to construction/seasonal/holiday route closures/deviations too, and so is transit.

[giantg2]

Road closure tends to be much more rare. Transit is much more variable in the US.