[EVO X]

Not sure where you are getting your figures from. In my part of fly over country the price difference between regular(87) and premium(93) can be close to a dollar at times. Regular is $3.50 a gallon. Not much different from about a year ago.

[Angelino97]

It was at a Sinclair station. Only 10 cents differential between the various grades.

It seems to be normal in Los Angeles. I found this photo, taken at a Los Angeles station (I don't know when).