That piracy causes client damages is a debatable point. Studies have shown those who pirate software, movies, television, etc., will rarely use or consume that content if they didn't pirate it. I know way back when, when I pirated stuff voraciously, if I couldn't find something I just never read/saw/used it. Not once in my life have I spent days or weeks trying to pirate something only to turn around and pay for it. Some (not all) studies even show that in the case of software, piracy in some cases leads to legitimate use, i.e. purchasing.

Now there's no doubt that piracy violates copyright law. We can debate whether or not that's a good thing, whether the laws in question are just, etc., until the end of time. But it's not a foregone conclusion that piracy has any negative economic impact on copyright holders.