Exactly. Here in Denver the grades are 85 87 89. My car needs 87. If I try to operate with 85 it feels like a person trying to go jogging on an empty stomach. Just not enough energy.
I use cheap 85 octane in my 87 octane vehicle and don’t notice difference. The top tier have the most additives. It would be nice for the to take the junk alcohol out. My old tractor requires good 60 octane gas and I can not find any.