not sure if its in the public domain yet, but when these microstamping bills were originally introduced around the country, the microstamping technology was under patent, and all belonged to ONE COMPANY!
Now, there is very little that is better for your business than to have the government pass a law that other manufacturers and purchasers MUST buy & use YOUR PATENTED product!
I think if you do a little looking you would find some connections between the people pushing these laws and the people who own the technology.
Follow the money.
All else being equal (and it almost never is) bigger bullets tend to work better.