From a reader at one of the big oil companies:

Most of what are called “subsidies” of oil and gas producers in the US are simply the same tax credits and deductions to which every manufacturing business is entitled: depreciation, inventory accounting, etc. Stripping out these provisions only for companies in the oil and gas business singles them out to be treated worse than other industries. All we ask for is a level playing field: no special favors, no special penalties.