I think we may be talking past each other.
People fake money, because then they can spend more money than they have.
There really aren't any benefits to faking being in the military of a certain rank.
People WILL check you paperwork in the military, when you show up. I'm not going to just do whatever some random Lt Col tells me, unless I KNOW who they are.
It's like being in school. Your teacher expects certain students to be there. If they see someone they don't know, they find out why.
There is literally no reason to protect insignia from being produced by whomever. It holds no value by itself.