If your up in the front and running, yes. Not if you sit in the back. It's the same with literally any sport or activity.
The owning and operation of a paintball marker does not require any permits.
There is no record of any Incan sport of "paintball"
Yes, any material will reduce the impact of a paintball.
yes, to any gun made in the last 15 years
Just type in paintball to any search engine, and find a paintball field near you.
There are no "child" paintball teams anywhere.
any where on the internet
So far, i think its still only California.
no
There is no reason to put a paintball gun in a refrigerator, or any appliance for that mater.
There are no "kids paintball teams" anywhere.