To your first point of success = financial wealth: Some people believe that way and others don't, i'm a little in the middle. For me, if I could cure cancer for example but didn't become wealthy on it, i would still consider my life a great success. There are many ways one can gauge the successfulness of ones life. This gets more into a philosophical area.
To your second point: Now you're getting more into the fundamental reasons of the why people believe in religion or why does it have such a strong hold on much of society even in the face of scientific advancements of the last 100 years or so. Personally I think it began as humankind became aware of its own mortality. This logically lead to questions of what happens when we die. Rather than accept or even have the ability to imagine oblivion they concluded spirits and an afterlife. This would then naturally lead to the question of "what is the afterlife like". Combined with their answers that we got here by a god, they would then mentally construct the hierarchy of the afterlife. And so on and so on, eventually forming very complex religious belief systems. Each part of religious doctrines are there to answer some question we presented or to justify another part of the doctrine. Notice this is very similar to how complex delusions are formed in the minds of the mentally ill.
This is where intelligence plays a key role. The more intelligent a person is the more elaborate, complex and believable the delusions are. Most people default to those they perceive as more intelligent than themselves. Since the more intelligent people had come to these conclusions most people would think "if they believe this then it must be true". So in effect, the more intelligent people are the ones that were actually responsible for the overall advancement of religious doctrine. Of course now the trend is turning, with the majority of intelligent people leading the masses away from the ancient belief systems since they have more valid scientific information on which to base their new understanding of the universe.
There are also many psychological reasons for religous belief even in the face of more logical and rational explanations for everything. For example, desperation. In the face of some severe traumatic circumstance, people are more likely to believe as it is their minds way of dealing with the situation and it also gives them hope. Don't underestimate the need for people to have hope. Ever watched a show on some great human perserverance? Ever wonder how they could bear such a situation and still soldier on? It's because of hope even in the face of no reasonable reason to have any hope. This I believe is the greatest value of religion regardless of it's fundamental validity.
So, in conclusion, no, it is not retarded... it is human.