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xkcd #3167: Car Size
(imgs.xkcd.com)
Title text:
'They really shouldn't let those small cars drive in traffic. I worry I'm going to kill someone if I hit one! They should have to drive on the sidewalk, safely out of the way.'
Transcript:
Transcript will show once it’s been added to explainxkcd.com
Source: https://xkcd.com/3167/
Texas used to, maybe still does. You made me try to look it up and couldn't find a simple source. Plenty of states use MRSP or some measure of the vehicle's value.
Back in the day (Tulsa, OK) my friend had a 2-ton dump truck with antique tags (over 25-yo), paid $20. Meanwhile, someone buying a super-light Corvette was paying $650. (early 90s money)
I say go on weight, maybe some factoring of value. Registration fees are paying for roads, if your monster vehicle is doing more damage, you pay more.
Fuel taxes are paying for roads.
Subsidies are paying for roads.