When I think of the word normalcy I can't help but think of it as split into "normal sea". While it is often good to talk about things as though there were no real "normal", this is not the case. If you ask me to define "normal" and I tell you that normal, in the sense I am using it, means conforming to the standard or the common type (thank you dictionary.com). You might say that nobody really fits this description since everybody is quite different from everyone else and so there really is no "normal" but if you have a shuffled deck of cards there are 52! different configurations. You can't point to a particular configuration and say "that's the normal one!" it wouldn't make any sense. But intuitively what we mean is that a "normal" configuration is one that people would believe occurred by chance. If the deck is perfectly ordered 2 through ace and by suit we would probably conclude that the deck had been intentionally ordered that way.
While it is true that intrinsic to any such judgement of which card configurations are "random" (and therefore normal) and which ones are not is to put some sort of structure on the cards which is not fundamental to them as objects. Likewise I agree that there is no fundamental structure intrinsic to human beings which allows us to say what is "normal" however that does not rob the word of all meaning or use. To be normal means a great many things and to be abnormal has an even greater myriad of meanings. Rather ironically once we consider about 20 different independent criterion of "normal" the majority of people will end up being highly abnormal with respect to at least one of these criterion (assuming the standard bell curve).
I often times however observe the realm of "normal" wherein a vast sea of people live. It seems that as a group the majority of human beings strive for this concept of normalcy. To be normal is to have privilege and power, society bends to the will of the normal or at least to the will of what is percieved normal. In many ways what is normal is actually determined not by the general consistency of a populace but by the distribution of power within a culture.