As you already know from the marshmallow experiment (and all the variations done since), self-control in children turns out to be one of the best predictors of future life success. Whether the former is the cause of the latter, or whether both are effects of some other deeper set of causes is, to my knowledge, still an open question.
Still, will power is a useful skill to have, so Sesame Street is trying to teach kids some valuable lessons about fiscal responsibility, discipline and long-term planning and investment. Since their approach is inspired by the marshmallow experiment, Stephen Colbert decides to put it to the test and see whether he's destined for success:
Marshmallows and fluff... you can't beat that...