It appears that the extremely dubious claim of the existence of water on Mars is being used to generate more funding for the space agency and its many layers of hangers-on.
There are many unanswered technical problems with the supposition of the evidence of water there. That doesn't seem to deter the drummed-up ethusiasm for trying to find the evidence of life there. If they can just make that claim, they think they can expound evolution and refute the creation.
However, it is interesting that creationists would use that as a counterargument to continued exploration of Mars. Perhaps they don't care to consider explaining whatever evidence could be found away?