Two more comments:

1. There are distribution facilities here in Houston along the ship channel where the tankers fill up. The additives are put into the gas at that point. It may be a Shell or Exxon tanker but the additives are determined by to whom they are delivering that particular tanker.

2. As to long lasting cars: most of the folks on this forum are frugal and look for vehicles that will be with them for a long time and take care of them the way they do their tools. However, the vast majority of the driving public change cars almost as often as they change shirts and never encounter the long term effect of ethanol, additives (or lack of) and dirty oil. The manufactureres and refiners know this and that's the public they are selling to.

I am surpised (shouldn't be) at the number of people who never "own" a car. They just make payments forever, almost the same as a lease.