I wish people would stop shitting on detolfs. Do you those whom complain even have retail display cases? Why do I not see them in your photos? Can you tell us your experience in getting one? I sure never read about it here.
I looked up retail cases instructional videos and reviews, because yeah I WISH I could get one, but they require at least 2 people to assemble. Those with no friends or family will have to hire a taskrabbit or someone to help. And the cases that do come assembled are risky as you may get a shitty delivery guy by chance who can damage the glass or just leave it outside (they're supposed to bring it at a time when you're home).
Plus if you decide to move, that's more heavy duty/expensive hired help again in either unassembling it or having moving guys wrap and haul it whole. Detolfs in their boxes are fairly easy to move and assemble+unassemble. Not everyone is at the point in their life where they've purchased a permanent home, so detolfs, billys, and other minimalist shelves are a great option for non-homeowners.