It's bad for aluminum too. Actually, since 1985 just about every car has been made with e10 in mind, but even then e10 does reduce the life of the rubber parts (this is all rubber parts that come in contact with fuel at any point, not just those carrying fuel from the gas tank to the engine bay), just to within an acceptable range. E85 does MUCH more. Racecars that run on alcohol use different materials for parts that contact the fuel than those that run on gasoline for good reason.

Hell, during the past 2 years Chevron has spent $2 billion dollars trying to figure out how to make e10 not suck. Fun stuff this is. While the official line has been otherwise, I'm told internally GM had a shitstorm about warrantying engines for 10 years when e10 was to be used everywhere, and not just in the cornbelt.