Gasoline and diesel go bad because they are solutions of many hydrocarbons, and the lighter hydrocarbons are the first to evaporate, leaving a heavier-than-intended slurry of what's left plus accrued moisture from atmosphere.

It has little to nothing to do with bacterial growth.

'Fuel Stabilizer', additives that are intended to be added to tanks of vehicles which must have fuel sitting in them for prolonged periods, are oils which are designed to prevent the evaporation of the lighter hydrocarbons and prevent water infiltration; usually through the use of molecules that either bond with water readily, or by layering oil atop the fuel mass to encapsulate it from evaporation to atmosphere.

You didn't mention ethanol but that's what you mean. Normal gasoline is very stable, it's just the federally-mandated corn ethanol added to it that turns into sludge after a few months. Fuel stabilizer keeps that ethanol from degrading.

I would advise anyone with small engines, like lawnmowers or snowblowers, to seek out ethanol-free gasoline and use that exclusively in those engines.