Great point dude, also it seems that metal affinity is influenced by geographic location and the natural light cycle. The farther North, the less light you get in winter, which kind of pushes your psyche to a darker tone...it hasn't been studied, but you know how Scandinavia is such a cliché metal area? Where the grimmest of the grim dwell? Well, check this out: they have a HUGE problem with depression of the population. Their mental treatment facilities are filled to capacity with people who are depressed by the lack of light. This is why my aunt, a psychiatrist, is so successful over there - it's a very highly sought-after medical specialty.