As we all know, the Nintendo Famicom (the Japanese version of the NES, in case you were wondering) was pretty damn successful back in the day. In fact, it would be no exaggeration to state that the machine practically created the modern console market - certainly in Japan, at least.
Nintendo made a considerable amount of cash off the back of that cute little machine, and if a recent report from Japanese site IT Media Gamez is to be believed, it saved a packet on production by cannily cutting costs along the way.
The famous azuki red plastic was actually obtained cheaply, because at the time that particular colour cost less than other hues.
When you add in the wired controllers and lack of a "start" and "select" button on the second pad, it's clear that back in the '80s, Nintendo of Japan was just as keen to keep manufacturing costs low as its modern-day equivalent has been with the Wii and DS.
Useless trivia can be fun!