The general concept is “the cost of the price”. Which is something to consider for public goods. If the prices would be zero, the cost of a ticket system would also be zero.
The majority opinion is that we all pay for public works projects even if they don't benefit us, but for some reason, transit must be self-funded. It's odd, to say the least.
It is completely counter-productive and damaging to the economy and the environment, but it is not that odd, unfortunately.
Each resident/citizen can buy a public transport card, then tie it to their Gov ID and then tap it everywhere. You could argue that this could be replaced by some vision tech but I guess this is simpler and has dual use (visitors can purchase the card and pay instead of using for free).