
There is a problem with ventures that run in the millions and billions of dollars. That would be the source of the financing. They want to see a return on their investment. It is not unusual for industries to take years and sink seemingly unlimited amounts of money to achieve a return. Sometimes they fail. The cost of failed attempts mount up and eventually if there is no pay off it all gets scrapped or sold to the next investor hoping to learn from past efforts.
Traveling into space has been a for profit deal when satellites are placed into orbit. Everything else is exploration and experimentation. So far any talk of further trips to the moon or to Mars are as scientific ventures. To make that happen the financial incentive and reward need to be there. The Northrop Grumman Lunar Lander Challenge represents one effort to inspire competition to develop a system to deliver a vehicle for further lunar exploration.
Traveling into space is much like the expeditions that go up Mount Everest. The trip is long and faces extreme conditions. It requires a lot of equipment and support. Some of the people do not make it back. Also consider the few moon landings that have been made. Everest is littered with cast offs that the expeditions choose not to pack out. Things like oxygen tanks, camping equipment, bodies of fallen party members. On the moon are the bottom stages of the landing crafts, a lunar rover and other items.

http://spacegrant.nmsu.edu/lunarlegacies/artifactlist.html has a list of Apollo 11’s contributions to the lunar landfill. When all is said and done the efforts of high achievement will invariably leave its mark. Unfortunately we may find Mars suffering the same fate as Mount Everest, and the moon. It’s always cheaper and more feasible to leave the spent material behind. The Martians might want to consider going into the scrap business. With the Mars Lander they already have a start.