Luke, what you say has been said many times before and it is a valid point when faced with the high cost of losing life. But the simple fact is that we are explorers, we are curious about everything that exists around us. What we know of our Universe comes from our need to find answers and that will never change. Unfortunately the pioneers of this "extension of knowledge" sometimes become victims of the quest, but that is known by all participants.
You must not forget that manned space exploration is in its infancy, but it will continue, and it will bring rewards, perhaps not immediately to us, but certaintly to our descendants. The road to knowldege and understanding is filled with danger but thankfully it has not stopped us. Remember, where there is a mountain there will be someone ready to climb it, no matter how dangerous or costly it is.