A reseller is a wholesale buyer that buys fuel and sells it on without changing it. Jobbers and distributors are resellers.
A reseller sits in the middle of the chain, between the refiner that makes the fuel and the customer that finally burns it. It buys fuel in bulk and sells it on, in the same form it bought it. It does not refine the fuel or blend it into a new product.
What a reseller earns its keep on is moving and financing the fuel. It buys in large loads, breaks them into the sizes customers actually take, runs the delivery, carries the credit, and knows the local market. Jobbers and distributors do exactly this work.
The word also matters for tax. A reseller buys fuel to sell again rather than to use, so a sale to a reseller can be handled differently from a sale to an end user who burns it. That difference has to be documented, the same as any tax treatment based on how fuel is used.
In useAs a reseller, the jobber buys truckloads at the rack and sells them on to stations and fleets without ever changing the fuel itself.
See also Jobber, Dealer, Supplier