I know some adults that I won't trust them with a butter knife. 
They are adults that someone failed to instill responsibility in when they were kids and more easily trained.  A knife can be a great way to teach responsibility to a young skull full of mush.  Many kids nowdays are not given any responsibility till they're teenagers and then the parents complain and wonder what happened.  I think the fact that he's thinking about doing this and having some hands on with camping means his kid will rise up to the responsibility of knife ownership.