doing favours? I'm not so sure getting paid 3+ million dollars in the form of a signing bonus, to not play for a year, when you've already collected $18M of a $19M retirement contract, can really be construed as Marleau doing the Leafs a favour. If anything, the Leafs have done a hell of a lot more for Marleau than any other team in the league would have, and quite frankly, taking a $3M signing bonus then retiring is hardly a huge imposition.
And I suspect this was arranged from day 1. Look at the contract. They knew what they were doing.