Moon’s got no atmosphere so you can build a railgun to launch containers.

They still have to be caught, which will require a shit ton of fuel, but at least you cut it in half.

Maybe you can get the containers to collide. You shoot them to the lagrange point in opposite directions. All the energy could be input via railgun on the moon, then removed via well-timed collisions. Big cumple zones of foam or something would be necessary, unless you use stabilized magnetic repulsion. Heck they could slow each other down with laser beams if they had a big enough collector.

Then your engineering hurdle isn’t “How to produce fuel for 32,000 starship launches”, but rather “how to catch a flying container full of material” and you balance the momentum by sending other containers around the other way to meet it and get caught going the other direction.

And how to build a railgun on the moon for launching cargo containers. Not my idea, incidentally.

Who knows, it might even be good for our species to have some huge stretch goal to be pursuing in space.

Maybe the aliens will let us borrow some flying saucers and we can have it done in a month.