You should check the grade. Go by what the manufacturer recommends. My wife bought a Murano and it needed frequent top ups. On the forum I went to to know about what oil to use, all told me to go synthetic, 5W30. The car went on needing regular toping ups. One day I downloaded the Factory manual an guess what? Recommended oil is mineral 10W40. I went with it and the cars needs less toping ups, engine is less noisy and works better.
Unfortunately, adding a lot of oil does not mean you need to change it and the filter less often. They need to be changed because they get contaminated. Not sure the contamination goes away when the oil is burned. May be a bit of it.
