Viocjit, most of those places that you mention are rather remote territories insofar as the main body of populations are concerned. China for example, is the most populous country on earth and they have only a single digit percentage of followers of deistic religions. The Chinese do conform somewhat to the Confucian way of thought but there is no deity in that concept. Buddhists too occupy a large proportion of the worlds population. Buddhists have no single deity as monotheists do. You can not label either of them atheists but they simply have no singular god figure or any supernatural god figure at all.
The United states has a sizeable population, currently something on the order of 350 million. At one time a vast majority of our people were Christians or the catholic division of Christianity. Over time we have steadily lost our dedication to the Jesus figure. At this time some 40% of our population describe themselves as "nones". That description is to imply that those people when asked about their religious participation answers "none". They simply do not go to church or other religious ceremonies. That is not to imply that they are non believers. Many of the Nones do believe in the god figure. Somewhere near 20 percent of us are actual atheists or at least agnostics.
Go south of our continental border to Mexico, Guatemala, and then into Central America of Honduras, Nicarauga, Costa Rica, El Salvadore, you find a larger percentage of the people to be dedicated to the Catholic faith. Island nations like Haiti have some vastly different takes on religion. It is not uncommon for a sizeable proportion of Haitians to practice Voodoo. For them, there are demons who can be banished by burning sacrifices of goats, chickens and in rare cases humans, or the use of potent medicines like Marajuana.
The much shorter answer would be that the human race is fucked up with various, too often conflicting, closely held beliefs that transcend any semblance of rational thought. The emergence of non belief, atheism if you prefer, is alive and well among the more educated countries. It may take a hundred or more years for the majority of the human race to abandon the unsubstantiated beliefs in some kind of superior, omnipotent, being who lives someplace in the far reaches of our universe. In the meantime the more developed and educated countries are less and less inclined toward some kind of religious faith. It seems, curiously, that the counties in more northern latitudes are less interested in organized religions.................
