Raised higher for two reasons: To increase the angle for the lower light, and because it more natural to sit upright at barstool height than chair height. As far as the bookshelves, I have no idea. But it is a trendy thing right now.
IMO the pedoJoe shelves are different. The horizontal edges are less thick.
I pointed out the white bookcases awhile back. Still haven’t figured it out except it is “headquarters”?