I grew up in Orlando and lived without air conditioning until the late 60s. Obviously, I survived, but I remember having trouble sleeping due to heat and humidity on summer nights. Air conditioning makes it possible to sleep better and to be more productive during the days. Arguments to the contrary are just plain foolish.
What they aren't fond of pointing out is what percent of the earth's needs Americans produce with that same 5%.
Such as, for instance, 60% of the world's corn and 80% of the world's Durham wheat. Or the fact that there are more forests in New England today than there were in 1830.