My horses LOVE love LOVE corn oil - they will lick it off of my fingers but HATE hate HATE vegetable or canola. I guess they have their preference - there is a 'sprinkle on top' fat adder out there but I can't think of the name of it....it comes in a big gallon tub and you have to keep it in the fridge. That's HUGE to keep in the fridge unless you have a garage fridge for stuff. I do - it's the beer fridge / dewormer/vaccines/probiotics/etc... LOL!!
Maybe - I don't remember the name. Is it a powder that you top dress the feed with? I remember that it was supposed to be the next best thing to oil, if your horse didn't find oil to be palatable. But I remembered it would go rancid if you didn't keep it from getting hot - but you are right - I bet if it just sat in the house somewhere out of direct sunlight in room temp, it would probably survive.
I've used Cool Calories! I don't fridge it; just keep in the feed room, away from sun and excessive heat. Keeps fine. It's also sort of expensive (but not BAD). It's almost worth it, because it's easy and tasty.