On the contrary. Any natural beauty of the planet would be diminished by colonization. When I say natural beauty, I don't mean something that we can see and admire. I mean the beauty that is inherent to nature -- inherent to the way "God" set things up. Other factors notwithstanding, I think that's something worth preserving in itself. Colonization would simply adulterate Mars, destroying God's art with it.

Small price to pay in the quest for knowledge, though.