Bus drivers in general are absolute sour ****, they have a very strongly exaggerated sense of self importance. I bet she would have done the same if she's turned up with a £20 note. Anything is too much trouble for them.
There is an issue with this kind of generalisation.
To begin with a Driver carries hundreds of passengers a day on average....he is personally responsible for the money he takes in relation to the tickets and if he is short by 20p then he is responsible for making good on that...you might say,
"well what is only 20p?"...that is right, but then you consider just how many times someone comes up short and you can see a Driver being hundreds of pounds out of pocket each year.
Also there is the attitude issue.....many drivers are subjected to a whole range of insult and rudeness, from the casual to the personal, from passengers, pedestrians and other road users, often for simply doing their job and complying with legal and company regulations, it soon gets demoralising when you are abused regularly, add to this poor working conditions and long driving hours and you can see why some drivers are sourpusses on occasion.
As for this particular incident then I would never have left a vulnerable person at night alone, however you cannot blame the Driver, or the other passengers for what happened to her...the blame for that lies entirely with the rapist....if not her then I suspect that it would have been someone else that evening. Also the attitude of some people who give the incorrect change leaves much to be desired and while I am not judging this girl specifically, often it is the initial attitude of the passenger that forms the response form the driver.
Some operators have specific policies for dealing with this, some do not. I know this because I used to work in the industry and bought in policies that would cover this and related incidents such as not being able to cover change and children without the right money to get home etc....but this is not across the industry.