Carb issues

It sound to me like there are issues besides where the fuel is going.
You say that you use fluid to get it started, but it seems that if the fuel was actually going into the engine it would already have plenty of fuel in it and fluid would just make it worse.
Have you checked plugs to see if there is already to much fuel in it to start after it sits.
You can kinda see whats up if after it sits like that if you crank it like you would normally want it to start. (like 3 seconds) then pull a plug or two and see if they are wet.
Your issue sounds more like a fuel starvation problem, and I'd bet those plugs are dry.
Also, if you were loosing that much fuel into the engine it would have a gas smell to the oil.
Does it?