Yes, In Michigan there is and it because of taxes.. Add around 50 cents to a gallon..
Road fuel is state and fed taxed, home heating and farming is not so taxed.
Running home heating fuel in an on road truck is tax evasion. Your local supplier may be obligated to report or may not sell to you if you are not using it for home heating or risk tax problems himself, at least in Michigan..
The gov't makes the distributor collect the tax or justify why is not collected.
For instance, I have a sales tax license. If I sell to anyone who is not legally allowed to claim exhemption, I am liable for the tax. Of those that are, I have to have a legal document signed by them (under perjury penalty) requesting an exhemption and on what grounds.