Oil will be going one of 3 places. Outside the engine in the form of a leak, inside the engine in the form of burning oil, or into the cooling system (blown head gasket). It will not just magically disappear.

If the engine is consuming the oil at the rate you claim, you'll smell it. You bet. You'll also have that blue haze out the exhaust pipe. A possibility is that you have a turbo seal that's bad, and it's dumping in the cat or muffler. You'd expect to have smoke or power loss issues if so.