Yes, we are in fact brought up to do all those intelligent things and act as if we were coherent with the norms of the society, but if actually left to ourselves, with no one around to judge us, would we do things the way we do them with a score of absolutely unnecessarily interested eyes making note of our every movement? Left to myself, I would probably move about naked, take a dip in some river or pool when the sun was at its highest, not care whether I was putting on weight, eat each and everything that I considered edible in a fashion that is disapproved of, lie around all day doing nothing or walk around aimlessly. Now imagine such a person lazing in the garden next to your room. Scandalising! And I am pretty (though not completely) sure that such a lunatic lives inside each of us.
Perhaps it is better that the lunatic remain inside. Not because otherwise the world would become a anarchic and uncivilised place, for it really is not as civilised as it pretends to be, but because if we become the lunatic, we would not have an asylum to run to. Albeit all the pompous fairies around us hold us in contempt, we do from time to time resort to such limited lunatic behaviour. Gluttony at times of depression, skinny dips for the thrill of it, lazing in the middle of the day to take a break from the hectic routines, dancing without steps with a goofy smile stuck on your face. It is all exhilarating. But like all good things, too much of it would rob you of the occasional pleasure that you derive of it.
There is a necessity of insanity. Almost as necessary as is the existence of a sober pretense to cover it up. But to hold a fellow man in contempt when he is blissfully enjoying his lack of restraint or to share his intoxication, if only a little; that is the question (for it is an absolute requirement that there be a question. As is the case with every other things, there has to be a point to everything. Otherwise it will be as pointless as life itself).