My last several cars required premium fuel. When I finally switched to a truck that ate 87 Octane, my wife switched to an SUV that requires 93. (technically 91, I think, but it gets 93).
Honestly it wasn't that much of a difference back when I started with the Mustang (Unlike your wife's, mine did require 93 or it would detonate) Back then it was like 20 or 30 cents a gal more, so not that big a deal. Now it's like 60 cents a gal difference. That's like $10 for the wife's tank. But even that isn't that much when you start looking at the price of "fast car" brakes, tires, and other consumables.
[shrug] You gotta pay money for a performance car.