Engines can't help but to burn some oil, if they didn't that would be a sign the cylinders weren't getting a good film on them. On a car the manuals often state that up to a quart between changes is acceptable even when new but what with recommended 3,000 mile changes I'd call that excessive, they're just covering their a** for the oddballs that aren't in perfect tolerance as well as making others feel they've got an exceptional one if it's less.