You might have a legitimate problem with taxi drivers and taxi owners because of their on and off violence, erratic driving, inconsideration of other road users, etc. You might be justified with the unfairness of people like you and I of having to pay for the toll roads while taxi owners and taxi drivers ride for free. What you must bear in mind though is that there are +/- 15 passengers on that taxi. There are +/- 15 people who just want to go to work so that at the end of the month they can get paid so they can feed their families. The reason why government and SANRAL decided not to let taxis and buses pay is not because they (government) are afraid of taxis, it's not because of taxi owners and drivers themselves at all, it's about the passengers. Its about the passengers who are poor already and further burdening them will have unintended consequences.
You say taxis must be taxed, fair enough. But why aren't churches taxed?
The point I was making about people like you and me who are lucky enough to have jobs and skills is that we are better off than poor people who use taxis on a daily basis. I also earn a modest salary, I share a 2 bedroom apartment with someone which means I can't afford to buy a house. But it is possible to free up R550 a month.