There’s probably less wear and tear on the belt when it stops like that, which might be a factor too. If all the bags fit on the belt like that then maybe this mode of operation is preferable to passengers so that you don’t risk “missing” your bag and waiting for it to go behind the wall and come back out again.

Somewhere (at a regional airport in the US but I can’t remember where) I’ve seen a baggage claim belt that is just a single straight conveyor belt coming out of the wall and ending in the middle of the baggage claim area without any return (so if it ran too long, bags would theoretically fall off on the floor). I assume it was used just for small regional flights where there would be an upper limit on checked bags, and so the belt would run until all the bags are landslide, and then stop.