I'm not an expert in the field, but I found
this. It says Ohio doesn't do it, but I know they're always freaked out at my company at year end about making sure we don't overstate the amount of fuel we have sitting in our fuel tanks. Not sure if that's why.

we don’t overstate the amount of fuel we have sitting in our fuel tanks. Not sure if that’s why.
It is also part of the calculation for income tax.