There is basically no difference in gasoline "quality" today, it's not been a thing since the 90's. As long as you're using the correct octane, your car will be fine.

Thank you for that info but that wasn't what I asked.

I thought I saw GetGo on the Top Tier website a while back, I'm reasonably sure. They're not on the list right now. But the GetGo website (copyright 2021 lol) says they are. I don't shop there because their prices are always well above adjacent stations, and Costco carries Top Tier so much cheaper that the membership paid for itself for me in gasoline alone in 4 months. Maybe others who frequent other GetGo pumps know the verdict.

It's because literally nothing is going on. They took down fluff.

Disagree. Quality gasoline has additives to help your engine from buildup on internal parts. Top tier gasolines meet a certain criteria to be labeled as such.

How do the additives differ from the fuel injector cleaners you can add to your tank like stp? Just something I’ve always wondered about.

How many people do you know that needed a fuel system clean out from not using top tier gasoline? The answer is zero.

I keep track of my mileage. I notice that it can make 40-60 miles difference depending on which gas station I get it from.

That is a huge variation and seems highly unlikely to be caused by type of gas. The more likely explanation is different driving mix between city and highway

Do you think the ppl who have performance issues and premature engine wear are able to unequivocally identify the root cause?