@datarama there was a great joke in Divine Divinity on this:
P: What is the reason for the relatively small stature of dwarven people?
H: It's an economy measure. If we were any taller, we'd have to dig bigger tunnels to get about.
P: How tall can dwarves grow?
H: There was once a dwarf who never drank mead or ale. Poor bugger grew to the height of four dwarves on top of each other. That's why we dwarves drink alcohol from birth - to stunt our growth to a decent size.