It does make you wonder that at age 16 you are old enough to drive a car, get a job, pay tax, run a company, join the army, die on a battlefield, marry, have hetero and homo sex.
In New Zealand there are a few things you can't do at age 16 such as watching a porn movie (presumably you don't need to get into the mood at that age, or what?), smoking cigarettes or joints, having a beer, or voting. Now in the UK, what with all the election campaigning going on, there are demands to reduce the voting age to 16. A good idea, methinks, and while you're at it, make those other activities R16 too - perhaps with the exception of driving, which should be restricted to IQ 100+ rather than to a particular age.