Every other tank or so, I pour most of it in the gas tank and leave a couple of ounces in the can and put in the oil. Once or twice a year, I do the same with MMO.
They are about the only examples of "Snake Oil" that I use.
In the fall before I leave, I put a can in the tank, fill the car with no alcohol gas, and drive directly to my shop. After the car has been tucked away, I fill the gas tank to the brim from a fresh can of non-alcohol gas to eliminate as much air in the tank as I can. I have never had a fuel problem doing that.