Of course, most 2-stroke engines require oil to be mixed with the fuel (I appreciate there are 2-stroke engines that don't require this). Therefore, it makes sense to me that oil will be burnt during the combustion process, given it is mixed with the fuel.
However, what doesn't make sense to me is why 4-stroke engines don't burn just as much oil. In both engines, my understanding is that the oil has to be used within the cylinders to keep them from seizing, so surely a 4-stroke engine would also be burning oil too, with the oil just being added at a different stage?
I would like to understand why 2-stroke engines burn more oil than 4-stroke engines?