I think your own view that every game pirated is a lost sale is equally naive, so, to each his own.

I certainly don't believe this, but I doubt that the "I only pirate games to try them before buying" crowd is terribly large either. even fewer people are going to actually buy the game first and then download a pirated .exe to replace the original.

That group is not large but they weren't buyers to start with so they aren't counted as lost sales.