You know, the age of majority does tend to vary from place to place even within a single world...

*or even be different for different things in the same country--you can marry at 16 in Roland, but you can't legally drink alcohol until 20, go figure!*

But as for Pay Day, I've never had reason to make much use of it myself, but as far as I'm aware the locals don't seem to question it, at least.