You miss the point. Pirating the game for any reason is stealing the property - period. Any loss of sale is loss revenue - if the product is on your PC, and you did not pay for it, they have lost the revenue. There are countless examples of people playing pirated games their friends gave them - it's just so very common. Game making is a business - stealing the product for any reason is wrong and lame - I don't blame a buisness for abandoning a market that continuously steals from it.
You (everyone who downplays piracy) don't deserve good PC games.
Shhh! Jojo, people don't want to hear that around here. They are simply borrowing a game that they were never going to buy in the first place. True, they do the typical things you would normally do with a paid-for game - namely play it. But really, they had no intentions of buying it anyway so they shouldn't be expected to pay to play it. All is well. There are no lost sales. Not one. There are no victims. Game makers are charitable folks at heart and are not interested in profits. In the future, please think before you type such nonsense.
By the way, for the clueless around here (i.e. most everyone one this board), the above was sarcasm.