I had a reason for that non-sensible move many years ago. Around 1991 I lived in the So-Cal desert Antelope Valley. My wife was driving her 70 Chrysler 300 2dr, one afternoon she came home complaining that her car kept dying every time she stopped. So I took it for a short drive and it was running rough and wouldn't idle in gear at all. She had put gas in it earlier that day at an ARCO station. So I drove into town with it having about 1/2 tank of gas and filled it up at the Chevron station. Drove it home (about 15 miles) and it was running fine by the time I got home. A few months later I gassed up at a different ARCO with my 68 barracuda 318 and had the same result, wouldn't idle, ran rough, once I had room in the tank I filled up with Chevron and problem solved. Then of course being hard headed and cheap I put some ARCO gas in my 70 Ford F 250 with a 460 in it.. you guessed it same result, wouldn't idle ran rough. next day dumped in some Chevron gas and bingo problem solved. About 1 year later my wife was complaining about her car stalling and I asked where she got gas, she turned red faced and remembered I has asked her not to use ARCO anymore, she had forgotten. Put in good gas problem solved. I always look for the cheap gas to this day and will put any brand in our cars, no problems. Except I won't buy ARCO gas again. They don't sell that crap in my area anyway (Ohio). I have no idea why our cars at the time wouldn't run on that stuff but it did force me into the high priced Chevron for a cure. And KD I am with you, it makes no sense to me to buy overpriced gas if your cars run the same with the cheap stuff. ARCO excepted of course.