Because most people aren’t going to mount anchors in their ceilings and lift 5 kilos every half hour for a paltry 5-10 lumens.
Even for emergency purposes, I wouldn’t purchase these lights. I’m not sure how many 26650s, 18650s, 18350s, 16340s, 14500s, 10440s, plus a litany of NiMH cells that I happen to have on hand in various states of charge; but I’m sure that I’ve got more than enough to supply a couple hundred lumens for over thirty nights. I could stretch that to over a year at 10 lumens. And in a real pinch, I could take one of these from off my gatepost.