There is the obvious answer that the Spanish outlawed blades for 330+ years and so the blade was replaced with the stick. But if that was the only reason then why didn't all the masters abandon the stick and return to the blade once the ban was lifted? Why don't WE return to the blade?
Balintawak has more to teach us then just stick fighting. Balintawak is a way of life.
Balintawak may look different from system to system and between individuals in any given system but its essence is the same. After all, we are all swimming in the same ocean even if we are wading in from different shores. Your perspective is unique and it is what you have to offer. Take it seriously.
There are 2 sets of reasons why I train Balintawak: Pragmatic and Philosophical. Pragmatically speaking, it was there. It's a lackluster answer but it's honest. Philosophically, things are a little more complex though not particularly complicated.