I'm not a big fan of E10, either. Those particular engines aren't optimized to make use of the EToH in the blend. Problem is E85 cannot be piped to the pumps, it has to be trucked, so the E85 pumps aren't far from the distilleries. That means E85 isn't popular in non-corn states, and probably does need mandates and subsidies when the local market doesn't support it. I can't see Texas and other arid states getting on board with it, at least not until cellulosic EToH kicks in in the not-too-distant future. I see that Florida is working on using palmetto as the feedstock, more power to them, I hate that stuff. Maybe somebody can do the same with kudzu?
Mind you, I'm a "fuelie" from way back in my brother's and my Mopar Hemi days. As a kid, my old John Deere Model B ran on kerosene in the front main tank, with a smaller rear gasoline tank for starting. My dad and I played with all sorts of combinations in that front tank, with results ranging from dismal to surprisingly good.
Likewise, when I built a go-kart with Continental engine at 12 years old, my dad rationed my gasoline usage. (I was a terror on that thing) My kid sister got her ears pierced, and received several bottles of isopropyl rubbing alcohol to keep things sterile. She didn't need it all, and the more she used, the more Mom bought her. I liked the neat blue flame that came out of my go-kart's exhaust.
If I can figure out how to re-jet my Shovelhead XLH, and swap out the rubber fuel lines with stainless, I'll run E85 in that, too. The compression is high enough to make things very interesting.
My next-door neighbor drives an older Volvo diesel. He's got a sweetheart deal with a local restaurant, and gets their waste cooking oil for free. Considering how popular Friday fish fries are here, I'm considering finding a pet restaurant myself, and an older Mercedes or Volvo diesel. Again, not the solution for everybody, but I'll do my part to make sure that big SUV drivers don't run short.