UPDATE !!!
So I started asking if centerfold was attached on this book before purchasing on ebay. Three different sellers looked and found out that their B&B 60 did indeed have a detached centerfold, one of them lowered the price enough that I grabbed it anyway. I also came across a copy right before it was ending and went ahead and took a chance. Of course, loose centerfold . There was the the boardie selling a VG copy that I asked to check the centerfold for me, after checking he did a light pull on the page and is now the proud owner of a loose centerfold copy!! I now own 8 copies with 7 of them having completely loose or loose at 1 staple centerfolds.
I'm going to go ahead and say that this is common on this book. At this point I think CGC should just consider it a printing defect and not deduct for it.