Or why not launch from the water directly? https://en.wikipedia.org/wiki/Sea_Dragon_(rocket) https://en.wikipedia.org/wiki/Sea_Dragon_(rocket) More practically

Or why not launch from the water directly? https://en.wikipedia.org/wiki/Sea_Dragon_(rocket) https://en.wikipedia.org/wiki/Sea_Dragon_(rocket) More practically for Starship, I think one problem with the wharf idea is that you need to get a 5000t rocket there. Not unsolvable, but expensive. In fact, the problem isn't that making a launch pad that is able to withstand the thrust of Starship is impossible, they could have simply copied the Saturn V launch pad design. But the Saturn V launch pad design is (intentionally, for historical reasons) way overbuilt and expensive, prompting SpaceX to attempt a more economical solution.