may have something to do with Break-in of the engine.
Some M3 owners burn a quart a month, while others never burn a drop.
I am in the latter group... no oil consumption in the 2 years I have owned her and eventually i stopped checking the level every week.
I am forced to admit I check it about once a month now... hangs head in shame.
Still keep a full bottle in the trunk anyway.
Life is like a B Movie, you wouldn't want to sit through it twice, but you'd hate to leave it in the middle!