It might, but quality control gets more complicated with PODs located in the US. I want this to look good, and the only way to assure that is to eyeball the books before they get mailed to me (and they have to get mailed to me at some point, even if it's just a preview copy).
I'm open-minded about POD, or at least more than I used to be. But if I went with a POD-type printer, I'd go with one in Europe as most of my sign-ups so far are from here.