The original octane rating is all well and good, but these folks aren't using higher octane willy-nilly, they're doing it in order to avoid damage from pinging engines. Here one dealer is saying I can't fix the pinging, but at the same time you can't use the fix of running with higher octane fuel. I can see how that would be very frustrating.
Chrysler for a few years engineered an engine that pinginged as part of its normal operation. They called it "the sound of economy", or something like that, because it was due in part to how lean the engine ran. The Pro ain't supposed to do that, though, and it can quite damaging to the engine. Here's some reading on the topic FYI: