DodoGeo: While I expected them to sell keys for Steam, but this put some perspective on said service.
It shows that publishers have influence over the prices of their products and it explains why COD for example never drops it's price and a sale is 33% off max.
I believe more and more that AAA game publishers are also at the root of the $=Euro problem as more and more indie devs avoid such pricing.
I never really had much doubt about this. It's pretty obvious when you see that dollar to euro pricing is pretty publisher specific. Same with the sales. Some, like Activision, are infamous for hardly ever having sales or always having it on low sales percentages.
If Steam had any direct say those games would probably gone on higher sales long ago.
What I do think they do is make it 1:1 Dollar to Euro unless otherwise specified by the publisher. There's plenty of cases where games are priced fairly Euro vs Dollar but others aren't. So if a publisher says to Steam 'Sell our game for $9.99" they'll probably put it up for €9.99 unless they are told to otherwise.
I do think Steam plays a big part in advising price though. They have tons of metrics and experience when it comes to sales so they probably make a lot of recommendations on what they think would be the best way to profit from a product.