Is it normal that our cars eat oil? I wouldn't say mine burns it necessarily, but it seems that every 2-3k miles I have to add a quart and a half or so to keep the level up. Is this normal?

The owner's manual states that "oil consumption up to a quart every 3000 miles" is normal and should be expected. Wear and tear can agravate the situation, as can any oil leaks you may have.