I didn't say that vehicle taxes alone paid for the roads, but they do represent a significant portion of the funding for roads in the US. And vehicle taxes/user fees cover a wide number of fees; licensing, registration, gas taxes, tolls, ...

I work as a transportation planner, I know what I'm talking about (at least in the US). The bottom line is that cyclists in the US pay little to nothing for the infrastructure they use. Its not ridiculous, its a simple fact.