I found that even if none of your "faces" are checked off in the photo sync section of itunes you still end up with some in the faces album. These pictures are from albums you selected from your Mac to be brought to your iPhone, forcing the iPhone to have the Faces Album. If you go into the unwanted album and figure out which photos are being synced to faces, you have a couple options:
1. Delete the pictures from the original album on your computer and re sync
2. screenshot or modify in anyway to keep the photo on your phone, then apply step 1
3. (not sure if it worked, I used 1,2) untag the faces from those specific pictures and re sync
hope this helps