sounds good until you pump in 9 gallons of bad gas....if you’re on a trip far away from home....how are you going to get rid of 9 gallons of bad gas? Your trip will be over ending with a tow truck and a long stay in a garage. Costing hundreds of dollars. Been there and done that. I’m speaking from experience not hypothetical. Only my experience was with 30 gallons of bad gas. Which is all the more reason to always buy from national chain gas stations. Not the cheapest place in town. And high octane.
In 40 plus years that has never happened to me so I refuse to live in fear of it. But then again I won't get the flu shot either...