I have 62000 on my Lacrosse and I have never had to add oil. But a relative had a Cadillac with the 3.6 and on a trip to Florida he about lost his engine because it burned so much oil.
I have read that the rings will stick but if you do hard acceleration several times that it will free the rings up and quit burning oil.
I do not have that problem because winding the engine up is quite fun.