This actually appears in music much more than games.

With music, discovery is a major problem, and pirating allows for music to be heard by a larger audience. Some of those people become fans and ultimately buy tickets to concerts (artists accrete more money this way, incidentally)

When you bought it one year later, did you pay the full price of it as it cost 1 year ago when you actually played it, or did you buy 2 licenses at a highly discounted rate on one of the frequent steam sales?

If you have 200 game developers slaving away to push out a to push out a 50-EUR game, pirating and then a year later buying it at a 10-EUR sale will not do them as much good.

Only true if the 50-EUR sale would have been made instead. This is RIAA logic to suggest that every single download is a lost sale. If they would have made 0-EUR out of him with no piracy then piracy hasn't really lost them anything. Besides, they only charge 50-EUR as part of a market segmentation strategy ie so they can get more money from people who would pay more.

Buzz is important, and products like games are heavily buzz-dependent. Piracy exposes more people to your product and generates that buzz.

However, while hardware manufacturers give out latest hardware to reviewers in order to generate buzz, they don't just hand out alienware laptops in the local mall. I think piracy needs to be tedious, unreliable and a compromise to the genuine game for it to be effective.