Just a guess, but the stations that are most likely to do this would be the independent ones; the stations that have surprisingly low prices (relative to nearby gas stations) I would think.
Here is the biggest problem with small independent gas stations - they can’t stand behind their product.
Here in town, a local chain accidentally had water in the gas. They put flyers up and advertised on tv: if you used our pumps, take your car in to get inspected/repaired...and we will pay for it. That’s great - they preserved their reputation and stood behind their product.
Around the same time, my stepson put gas in my truck at an independent station...and the underground tanks ran dry. That’s right...the station ran out of gas, and all the rust and other crap in that tank went into my truck. They were running on a shoe-string. Do you think they would have paid a nickel, if my fuel pump went out?
It did go out a few years later...but they’re long out of business.