I'm going to piggyback on benyben's question here.
I understand that by doing this, we secure the network, however, here's my question: WHY are we being "paid"? Is it because we are securing this network?
In a way, yes. But mostly because any monetary system has to have the initial distribution somehow, and distributing the currency based on the contributions towards blockchain security is about the most equitable as can be devised for an anonymous, digital currency. Eventually that initial distribution cycle will taper to zero, and then miners will be "paid" to process transactions, but the method of processing transactions also contributes to the ongoing security of the blockchain in like manner.