Go have a look what percentage of the operating costs are covered by fares in your city. I wouldn't be surprised if the costs relating to fare enforcement were more than the revenue from fares.
You aren't taking into account that transport agencies can raise a lot of funding based on yearly revenue so multiplying fares out in terms of the debt that can be serviced yearly can easily reach billions which can be used for capital investment.
You aren't taking into account that transport agencies can raise a lot of funding based on yearly revenue so multiplying fares out in terms of the debt that can be serviced yearly can easily reach billions which can be used for capital investment.