When I first read "Pascal's wager", I honestly didn't have a clue what that entailed, so I decided to do some research. For those that didn't have a clue, like me, here's a summation of Blaise Pascal's wager (from wikipedia):
"Even though the existence of God cannot be determined through reason, a person should "wager" as though God exists, because so living has everything to gain, and nothing to lose"
This doesn't really sit well for me. For one, notionally, anything can exist. Each human can construct their own notion of "God", just as they can construct any other notion. In fact, culturally, the notions of "God" vary sometimes diametrically in their 'being', not even taking into account individual thought. So, to some, "God" can be determined through reason. Why? Because you can meld the notion of "God" the way you see fit, and many do. This means then that Pascal is already applying his notion of "God"; the wager is inherently flawed. Moreover, even if someone did have a notion of "God" that was identical to his, by a long shot, probability theory shouldn't be involved as it appears to be contradictory to his 'wager'. To involve probability theory, which is essentially where the 'wager' is going, puts the basis of "God" on reason (the thing he just said God's existence couldn't be determined by)
This means that for any purpose, if there is an end to the metapurposes, then that purpose is nihilist and subsequently false, meaning that the only non-nihilist purposes must have an infinite cascade of metapurposes, which means that the ultimate purpose of our existence must remain infinite for it to remain true
It's impossible to have a meta-infinity-purpose for a mortal being, unless you're making the assumption that we live on in some way past biological existence. If you choose to believe we do not live on, there can most definitely be an end to a metapurpose - and it could the purpose of life. We apply meaning, and have the power to construct purpose to our consciousness. If someone spent their entire existence on this earth striving to become rich because of the aforementioned metapurposes in your post, that would be their purpose. If it wasn't their purpose, then what would you call the life they just led? Not their purpose? So, their existence was purposeless, as opposed to? None of this is even taking into account that you've streamlined the idea of purpose to fit this theory.
If we conclude that every action is made possible by self-intent, even if it's on the most subconscious of cognitive levels (there's a whole other thread on this, if you'd like to check it out), then every single one of those metapurposes has an ending. That is, no matter what one does, it can always lead back to desire, as we are a product of our desires, even if we aren't rationalizing the desire at the moment. And since essentially any desire is considered to be nihilistic and not worthy of purpose in this theory (since there would always be a metapurpose ending), no one is capable of having purpose.
And the purpose of a porpoise?
Very good point, I'm surprised people ignored this. Are you only applying this theory to humans that have a developed frontal lobe, or is every being, even those that may not even be able to rationalize a fraction we can, included? If other beings are, especially those not even capable of having the nihilist metapurposes you suggested, how do they fit into this theory? I mean, if we're trying to deduce the purpose of existence, we can't just begin and stop at humans, right?