Gas taxes are a very equitable way to go; a person pays more based on how much and how large of a vehicle they drive, and therefore the amount that they pay is proportional to the amount of damage they do to the road AND to the amount of infrastructure they require in the first place.

However, if we were paying enough gas tax to actually pay for roads, gas in the US would be probably on the order of $8 or $10 a gallon, and a U.S. politician would rather be caught eating babies than voting for a substantial gas tax hike.

As has been covered here before, bicycle riders actually pay for a disproportionate percentage of the road. Not only do they require a tiny fraction of the road both in terms of space and of expense (a bike-only road could be much narrower and built much lighter as it doesn't need to stand up to being crushed under tons of weight), but they do essentially zero damage to the road. Yet almost all bike riders also own cars and houses, and therefore are paying just as much property, income and registration tax as a car driver, but causing less wear on the system. Bicycle riders SUBSIDIZE car drivers.