Increase in Ethanol?

Did not know where to place this topic, let me know if it is not.
This was brought up at a car gathering. Talk got around to E-85 and how it could cause problems if used in classic and muscle cars. I know most use premium gas, in Michigan almost all gas has 10% ethanol, not enough to cause concern. There is talk of increase of ethanol in all gas without letting the public know, show it on the pump. Is anybody out there using an additive to there gas to make sure they have no issues. I have a 4 stroke outboard motor on a pontoon boat that requires an ethanol additive. The boat dealer said it's hard on the outboard motors, the boat also have a water separator. I burn premium in My 408 small block, no issues so far and I want to keep it that way. I've heard the additive used for outboards is not the answer for cars.

Tony In Mi