3 Loss, people are going to die and fail, its a sad and hard fact. The Vikings failed in building a base in the N.America, centuries later many sophisticated European colonies failed in the America's, Spain had failed colonial settlements, some English early colonies failed with Sir Frances Drake and England's explorers soldiers and settlers all returning back home. Bases may even battle each other and go to fight over resources, their could even be famines and cannibalism, in the early America's there were attacks on the French trading post of Port Royal and the Dutch colony of New Amsterdam, to survive some may be forced to survive as penal colonies. As painful as it is to admit the modern Western World might not have the stomach for planetary colonization, somewhere like China with its harsh communist authority and open free market system and high tech society might be better set up to colonize Mars and when you control the media you can afford to lose hundreds and don't have to worry about PR disasters. The Chinese might go for an ends justifies the means approach, if so they aren't going to be having moral or religious debates and would probably have little problem in genetic engineering or using people with robotic limbs etc
Fierstly, exploring the Earth is non-comparable with space exploration for the simple reason that we evolved here. This is our natural habitat. Secondly the Chinese are no less fond of their creature comforts than anyone else. It's not a racial or cultural call. Any pioneers would have to be highly trained, highly motivated and ultimately prepared for self-sacrifice.