There's no real justification for letting all the ocean resource projects continue given the long standing tragedy of the commons and how it aggravates naval turf wars. If we outlaw all of it we will be better off. We can move towards manufacturing sand-like construction filler from our normal glass system, which is able to consume land sand, and such a filler would be visually distinct from raw ocean sand.
And a curious side note, sand collectors... https://en.wikipedia.org/wiki/Arenophile