Just one example: If you want to go anywhere in space with chemical propulsion, most of your mass will likely be oxygen. For example oxygen-hydrogen rockets of

Just one example: If you want to go anywhere in space with chemical propulsion, most of your mass will likely be oxygen. For example oxygen-hydrogen rockets often have 6:1 mass ratio of oxygen to hydrogen. SpaceX Raptor has 3.6:1. Having a low delta vee source of oxygen is potentially extremely valuable. Hydrocarbons and water also are very useful.