The Olympics are not part of the commitment. One can demonstrate this by seeing that Roddick received a 0-point penalty for Washington, even if he played the Olympics the same week. That is because, Roddick needed all 3 remaining ATP 500 tournaments to fulfill his commitment. Monte Carlo is part of the commitment.
yes you're right : Roddick's case proves it
putting the Olympics result togther with the ATP500 results in the rankings breakdown is just a way to display the results (just as Monte-Carlo is displayed together with the mandatory Masters 1000 tournaments