A Falcon 9 launch produces comparable carbon emissions to a trans-Atlantic 777 flight. There are considerably more trans-Atlantic 777 flights than there are Falcon 9 launches.
Is the process expensive compared to just buying CH4 otherwise?
When Tesla announced superchargers, they were all about solar panels and cars powered by sunlight, but for the serious rollout they had to go with the more easily scalable, cheaper option, so very few superchargers have solar panels after all.