Also- it's a bunch of marketing crappola with regard to the octane... .
up here in the hills, octane is 2 steps below flatlanders (85, 87, 89-respectivly) because the same rating is not required due to altitude. But... 89 is considered "high octane" here and they charge for it! In my opinion... . 89 should be priced as 89 regarless of geographic location!
Folks up here are all in a tizzy 'cause the auto mfgr may state a minimum octane requirement when it is not available above a particular elevation.