Here in Brazil this is not to avoid fare, fare is chump change, it is to extort, or "repent". One case that I know, the woman had consensual sex with the driver, and got pregnant, her boyfriend dumped her, and then she accused the driver of rape. Happily for the driver she was a bad liar and contradicted herself many times, so the cops dropped the case.
Unfortunately, there is little evidence to go on at this point aside from her testimony, so much of this discussion is mere speculation.