Well, I said that it was entertaining for the reader - I liked it, but it didn’t “serve the plot”. I haven’t read The Afghan and so I can’t say if that’s similar or not.
But it did serve the plot. It revealed some huge, important to the plot secrets about the Moties that had been hinted at, but not stated.
By that point, all we knew was that Blaine’s fyunch(click) had gone insane, and all the Moties got upset when they learned that individual humans can actually live without breeding. During the mids adventure, we find out that Moties will die if they don’t breed, they constantly fight wars over resources and their society collapses on a very regular basis, AND they’ve got a warrior class that will beat the living shit out of the Imperial Marines. Really, really important stuff for the plot at the end of the book, when the Motie ambassadors are negotiating for rights to leave their system & settle the rest of the galaxy.
Heh, It’s a joke - of course the 1001 nights isn’t padding, but the whole purpose (as related by the framing story) is to delay resolution, since resolution = death for the authour. 
Zsofia, I get what you’re saying now - it had no bearing on the plot because the people involved, who received all the information that we, the readers needed, were unable to pass that information on to any other characters. I’d disagree with calling that padding though - I’d call it remarkably entertaining exposition.