I love manga artbooks. I don't have a huge number of them, but I do have a couple from artists that I don't follow anymore, or never followed to begin with, I just like their style. I also have manga and western comic omnibuses. I do my absolute best to keep all of them as pristine as possible, as opposed to my usual treatment of books (i.e beat the shit out of them). The nice condition of the artbooks and omnibuses adds to the pleasant experience I have when I read them.
I get collecting books as an object, but the object itself has to be worth collecting. I get buying a special edition that has illustrations etc that weren't in the early editions. I have spent large amounts of money and have spent months, even years, in one case nearly a decade and counting, hunting down certain books.
I don't get collecting multiple print editions of one book, all identical except for tiny variations on the cover. It does not satisfy any form of aesthetics, imho.