This is a common carbrain argument
“I already pay the gas tax”
The problem is that it’s false.
In a recent study, researchers Stefan Gössling, Jessica Kees, and Todd Litman calculated the social costs of driving. They found that the social cost is about 30-40% higher than what car owners are actually paying
https://www.sciencedirect.com/science/article/pii/S0921800921003943?via=ihub
That cost is paid by non-drivers.
Would you rather it be paid equally by all people, or would you rather people burning through gasoline and diesel themselves have to pay for more of the roads than yourself?
It seems a silly question, I know. But somehow you seem to have not understood it.