The Schwarzfahrer pun

Judging by the review by Polaris_DiB, this is one that non-German speakers don't get so I thought I'd quickly explain:
Schwarzfahrer literally translated means black rider but its actual meaning is ticket dodger.
So this movie has three Schwarzfahrer:

- the black man - the black rider

- the old woman - who is thought to be a ticket dodger after the black man eats her ticket

- the actual Schwarzfahrer/ticket dodger - the man with the helmet. From his reaction it is clear that he has no ticket. He is 'saved' by the ticket inspector finding someone else without a ticket first.

Polaris_DiB says that a character is introduced who has no purpose and I reckon it's the man with the helmet. But he actually does have a purpose, because he is the only real Schwarzfahrer.