In valleys with no services for 50 miles cell phones don't work and you can ride hours without being passed by a car.

Asking for a ride 50-100 miles from home, before sunrise, or long after sunset would be a huge imposition.

!@#$% tiny pieces of tire wire can elude detection and re-puncture tubes leading to multiple flats, sometimes slow enough you can get by with periodic re-inflation if you don't run out of CO2 cartridges.

Other riders also tend to puncture in the same places with some irresponsibly neglecting to bring supplies. I once saw 4 or 5 who flatted simultaneously.