Excellent philosophy, when faced with life's conundrums.
Answer by James Earl Adams III:
Indulge me the privilege of rephrasing the question.
"If you're going to run out of cake to eat, what's the purpose of eating cake?"
The purpose is to enjoy it. Having been served the above cake (or a flavor more to your liking, as you please), would you rebuff, "No thank you. There's not enough of this cake to eat forever, so there's no purpose to eating it." Of course not! Scarcity doesn't make it any less pleasurable.
Doesn't that cake look delicious? So it is with life.