Gas is Gas?

OK we all know oil companies refine crude oil then basically put it back in the shared 10" pipeline, then take it out of the pipeline 3 thousand miles away at various terminals, add their individual aditives which is basically the same as what every company has, then truck is to individual stations. The gas they take out of the pipeline maybe and most likely is another vendors gas. I filled up the today at a 76 station, my truck is running remarkably better today then its run in the last three months. I was specualing thats its the new un-oxygenated gas, I called the station, they said by law they have to sell oxygenated gas until the end of march. This is all really odd, I was getting alot of hesitation in my truck before today, I wonder what this could mean? Has the quality of the gas posible changed, I always just get regular. Before I was filling up at the same station and alternating between arco gas.