This is one of these suggestions that sounds reasonable and would be dreadful in practice. We should encourage people to cycle or take public transport. Cycling

This is one of these suggestions that sounds reasonable and would be dreadful in practice. We should encourage people to cycle or take public transport. Cycling frees up roads and makes people healthier. Charging cyclists would decrease cycling, disproportionately impact the poorest, and hurt public health (I'd make a case we should actually pay people to cycle). Likewise charging to use cars, in locations where there's no good public transit, would be terrible for the poor. The amount of damage done to roads by vehicles scales as something like the fourth power of weight at the axles, so the repair cost of cycling is nil, anyway. Everyone benefits from roads one way or the other, so the cost of roads and infrastructure should be spread. It's not an ethical issue, just a matter of who can afford to pay. Bill Gates profits greatly from his employees having infrastructure by which they can get to work, even if he doesn't drive. That's kind of the whole point of having a state.