If I buy a quart of Shell oil it plainly reads Shell on the label
The Shell gas station has shell on the pumps, on a huge sign on a pole, on the front of the station, etc. They brag about the gasoline on every pump you are filling your car from. Maybe some shady stations use non-Shell gasoline, but the test referenced indicated that whatever is actually put into the tanks at Top Tier gas stations, on average, produces a lot less deposits.