It would certainly add more things to use money on once you've bought all the exercise machines, if "upgrading/maintaining vehicles" is something you plan for an update.
I mean, the gifts are of negligible cost and there really isn't anything else to spend money on. Perhaps every so often, the player gets hit with some sort of money drain, like rent or bills or even machine maintainance for the top tier machines. Perhaps the chance to add cosmetic upgrades to the apartment..