Every time you fuel up a vehicle you are paying a "fare" to use the road. The fare is subsidized (just like with the bus), but it is very much there and not zero.
>Every time you earn money/spend money you are paying taxes.
>I guess busses run on fairy dust too?
Every vehicle on the roads is basically paying to be there via fuel tax (which in whole or large part is spent on the roads). Busses pass some of this cost on to their riders who's fare may be then subsidized in part or full.