And also sometimes it works as a sense of achievement, the tangible realisation of having done something right and reaping the results of it....... good for the morale and if taken in right spirit then act as a motivation to strive to continue to achieve more, to work harder so one can 'earn' more such experiences in life. It may also give the feeling of being rewarded for having been smart with your money, of achieving value from lower resources. It is the kind of twist you can give to it. While learning good financial habits may feel boring to kids, if they realise that the luxuries are a result of such smart habits, they may follow such habits as well.
I know - motivation, sense of achievement, success cannot and should not come from material things, but these are tangible things and work as great inspirations and positive influencers. Sometimes, inculcating some values and habits may take longer the traditional old fashioned way, but if tied to these temptations, it can be achieved a lot quicker.