Pulling ethanol out of gas

I don't know the whys and hows, but I do know that in the last few years, I've had relatives dropping off lawn mowers with carb problems. All of them, from leaving gas in them over the winter months (winter lawns are optional here). My Honda Ruckus has to be run every month or so to keep it's carb cleaned up. So I've started using additives. However, if someone uses my gas can and fills it up without me knowing, or I'm in a hurry and forget, I have pure fuel, no additives. Seems most are the jets getting clogged up. So either the gas is changing, or the carburetors are changing. Something is.