So this guy got nailed for not paying fuel taxes on his vegetable-oil powered car. Yes, appearently you can power your car with soybean oil. Anyway, the logic is that all fuels need to be taxed to raise road revenue, etc. Okay, I see that point but really, this setup doesn't make a lot of sense. Say you get a super fuel-efficient car that gets 200 mpg, you're certainly not paying your share then. It's kind of a use tax, but not really.
Anyway, how far does this go? I ride my bike to work a couple days a week. I'm clearly not using any gasoline in the process, and I am operating a vehicle. And I'm not paying fuel taxes. Heck, for my scrambled eggs I'm not even paying sales taxes!