SpaceX launches run 49.9 million dollars a pop, and Elon has stated that fuel and oxygen accounts for $200,000 of it. It's a surprising small amount, only 4% of launch costs. There is still obviously balancing to do, but fuel really is relatively cheap. Personally, I am all for having expensive parts that can be reclaimed, it makes it that much more important that you put parachutes on your early stages and recover as much as possible.