Evidence?
I think when someone states something like that, they have to really back it up with some kind of evidence. The lack of it merely makes it an opinion really, and given who he works for, it would be fair to assume a degree of prejudice against any company that is perhaps a threat.
It's also quite a clever policy. If he is saying that to be greener and cleaner and prolong the life of my car's engine, I should pay for the more expensive fuel, then that costs more. Which means I have to work more to cover the extra cost, which means, for a lot of people, more car journeys, more energy used at work, which means more greenhouse emissions...
If Petrol companies were REALLY concerned about being green, they'd make the better quality fuels the cheapest and offer free conversions to LPG or biofuels for car owners interested and motivated enough to make the change. Yep, it would eat into profits massively, but it's definitely green!
And totally idealistic of course, Capitalism doesn't work that way!