I've also seen people spamming the same deal for earpieces and implants, though less frequently. THAT one I don't understand as crits on those = augment slots, not extra units to sell.
It's a bit of work, but I guess it could make money. Make item yourself without augment slot. Have someone send you mats and hope to score a critical. Give the one without the augment to person. RE the augmented one and sell the augment slot components. It's small cash, but it could work.