I mean in speech, you can hear the difference. There's a very short stop between Fahrt- and -ende, whereas if it meant the rude version, it would roll through as one word instead of a compound word with two parts.
There a similar thing in Swedish with "tunnelbanan" - which means "the tunnel track" - their word for the underground metro system. Though there it's more an emphasis thing:
TUNnelBANan - the underground
TUNnelbaNAN - a tunnel banana
