Copyright information can be imbedded into the digital files by the photographer. This copyright information cannot be removed by copying or editing the files. When the photo lab opens the file(s) the copyright information will appear on their screen. Labs can be fined for printing copyrighted photos and most labs will not do it.
I give all my clients the copyrights to their photos in writing. There is no extra charge for this. I also do not imbed copyright information in the digital files.