Sexwarrior; you refer to "the ice wall" am i right in assuming that the general belief is that there is a large ice wall that prevents anyone actually getting to the edge? And for it to be generally un heard of to speculate what is beyond it seems a little ignorant in regards of the natural human instinct of knowledge.
And I actually feel that question number 4 was very important. There are many conspiracy theory behind many different aspects of the world. And behind every conspiracy theory there is always an advantage into successfully hiding the truth.
For example; aliens. The world leaders would have a lot to gain by successfully hiding the fact they do exists.
9/11, the world leaders need the public to believe this act was committed by extreme Islamic terrorists to keep support against the war on terror.
In contrast. There is no benefit (as far as I can see) of covering up the space travel fantasy. The knowledge we can gain from space travel and possibilities of being able to maintain life in space or even find another planet for humans to survive on is hugely advantageous.
My point being that it is would take a lot of resources and time to successfully mask the "illusion" of space travel without any real benefit. Whereas there is a lot to gain from genuine space travel.
It's not that we don't speculate what is beyond the ice wall, but that, as the sun only reaches so far, it is more-or-less impossible for humans to travel that far. So, while it is interesting to consider what may lie out there, it's just not something many of us consider all that important.
There are a few key reasons for faking space travel: money, greed, and power. For example, Lyndon B. Johnson, a former president of the United States, said this on outer space in his memoirs:
"Control of space means control of the world, far more certainly, far more totally than any control that has ever or could ever be achieved by weapons, or by troops of occupation."