Earlier I was critical of this design for a folding table. I argued it doesn't make sense as a bookshelf as it needs to stand in the middle of the room to be useful as a table, and requires the shelves be cleared of contents.

However, more recently designer Hongliang Qian realized it is the perfect configuration for his Rotating Table Service Robot. Current restaurant robot designs we've looked at have this form factor:

It would be awkward for a seated diner to attempt transferring plates from the lower shelf to the table, and thus a human server is still required, which kind of defeats the purpose. However, Qian's design adopts the mechanism of the bookshelf table to good effect:

Narrow enough to roll between tables, then unfurls to make unloading easier.

It's obviously just a concept, and sadly I was not able to find any substantial information about the designer.