I honestly don't know why this is so difficult for people to understand. Broken mechanics are broken. Justify their value or lack of value all you want it's still broken.
How is it "broken mechanics" when in essense it's more of a "trade off"? We can't create armor and gear for ourselves (save for implants) and crit them with augments. The money we save on purchasing stims/medpacs is spent on purchasing gear for ourselves and our companions.
The money YOU spend on purchasing stims (and let's face it, it's only stims you buy because medpacs from the vendor are just as good and no one sells medpacs on the GTN) is offset by the money you save by creating gear for yourself and your companions.