Let's say AC did sell certs for points. How much would they charge?
I would guess 5,000 absolute minimum for a N/A upgd, could be 30,000 - 50,000 for an international upgrade (SWU) one way . If you value points at 2c/mile you are better off going the eBay route...
Notwithstanding that, it would be a nice option to have.