I must be lucky, as my local (a few miles away) filling station has marked fuel, both gas and diesel, (sans road fuel tax) and the gasoline is premium, no ethanol.
I run it in all my small engines, and run them dry before storage, and have never had to service the carbs in the 8 seasons since I started doing this. I also mix my 2-stroke at about 30:1, both tactics come from my small-engine mechanic, who now just sells me parts as my small engines have been working so well based on his advice.
Ethanol is only a problem in engines that do not run very regularly. It will absorb water, which will support growth and foul the fuel system. It's fine for passenger vehicles, just not for small engines. My small engine mechanic does not like Seafoam for small engines, says it leaves more residue than it clears up.