I guess if a 20 A circuit is sufficient for the expected load that seems like the easiest way of doing this. Considering today's copper wire prices I'd really try not to bury any unnecessary wiring.
On a more general note: it's interesting to see how the regional and temporal perception of certain wiring methods differ!
For example, some areas of Germany were extremely fond of TN-C systems, i.e. neutral and earth bonded at each socket and light fixture with only two wire (L+PEN) distribution. In fact, electricians there were so convinced of the superiority of their method that they wouldn't use the blue wire even if they happened to install 2w+earth or even 3w+earth cable! They only used black and yellow/green, leaving the blue and brown open. Nowadays, most people frown upon this practice, for a broken PEN is a serious risk of electrocution and 1.5 mm2 or 2.5mm2 wires break much more often than 10 mm2 or larger.
The bottom line is: if you're absolutely used to something, you don't even question it any more, you just accept it.
