

We tend to distrust “free”.
I don’t think so.
Most people understand that free stuff offered by for-profits is sketchy and deceitful, while free public services is just another way of saying taxpayer-supported.
Everybody knows - or at least should know - that a free Google account means Google is going to invade your privacy, while enrolling for free at the local community college or attending school is their right because they paid for it in their taxes.
At least outside the US, that’s the deal most taxpayers understand they have with the state. In the US, people would like free public services but refuse to pay for it because communism or some equally stupid non-sequitur.
Then erect a small barrier to entry, like the need to request a PTA card to ride the bus - possibly for a flat one-time fee. No card, no ride, even though the ride itself is free. That should keep the problematic impulse riders at bay.