Defo 100% correct - I've had it on good authority (relative who works in the fuel industry) that different chains have different QC procedures. And different additives. I've heard Jet isn't the best, and one of the 'stories' is a mate who filled up with petrol, drove down the road and saw 3 cars who were at the pumps just before him, all broke down. Yup, diesel in the unleaded tank.... And a complete denial of the facts by the service station.
Of course, it's slander if I can't back it up with facts and dates etc, and I canne remember - so this is purely my OPINION....
Optimax.