Most of the small design studios - Treegloo, Portenzo, Pad and Qull, etc - can be easily overwhelmed by a sudden bump in orders, i.e. going from 50 cases a week to 5000 overnight, and there's a lot of pressure to meet that demand while not losing on quality and workmanship, as well as securing sufficient raw material (wood, vinyl, glue, linen and paper stock, etc) to produce these cases.
And because these cases are handmade to order, they have no "ready to ship" inventory lying around, and industrial/factory methods of ramping up production to meet short-term demand don't apply, i.e. if a craftsman can only make X cases in one day, then any more than X orders daily will generate a constantly increasing backlog.
I suppose they could do a better job of managing customer expectations, e.g. "Quality handmade products take time. If you order one now, it can take up to 6-8 weeks for us to get around to your order - please don't bother us until at least 8 weeks have passed, and we'll let you know when your item is ready to ship." I think customers, if kept apprised of how their orders are progressing in the queue, are generally happy to wait, esp if they know they are getting a unique, quality product at the end.