Patrick, I think it depends on the type of client. I used to shoot portraits for a living and none of my clients would have dreamt of getting images copied, but the middle to lower end of the market is different now. I made my money mainly on the fees, rather than loading the print prices. I still do the same with commercial work.
Even before digital images were copied, Kodak had a direct copy colour print process that Pro labs offered, many turned a blind eye to copyright or made the customer sign a waiver to protect themselves (the lab).