Maybe they're comfortable some places, but they're a ridiculous piece of clothing the majority of the year in the US. Living in Atlanta, I've made it a goal to wear a suit as little as possible as I find myself hot/sweaty in all but the deepest parts of winter.

I feel the whole concept of a suit is quite out of place in a modern world where climate controlled buildings are the rule rather than the exception and most business/frufru social events happen within them.