It's not as easily found in certain places and it's not convenient and people dislike change when they think they can fix their problems by tightening different bolts.
Around here I have to drive to a semi congested area of town (next to the airport) that's not even on the way from any place I work, therefor I never bought aircraft grade fuel for my motorized bike even though I could have done it any day of the week on a whim, just because, in the last few years.
At most I'd do it for a weedwhacker or a chainsaw gas can, just because the ethanol free fuel doesn't absorb water nearly as easily though, this makes storing it in a shed or garage a bit more stable if you just don't use the fuel as often.