I agree with you. The idea of "mining" these numbers using an ever-increasing amount of computing power is simply absurd. They'd have done better to allocate the coins in some other way .. I don't know how, maybe distributed equally among Hacker News readers? That would be as good as anything, to get the system started.
You misunderstand the purpose of mining (which is really a misnomer). It is necessary to do a distributed, hard-to-manipulate verification of transactions. Creating new bitcoins is just tied to it as an incentive. "Mining" will continue after there are no more new bitcoins. The incentive will change to transaction fees.
