XmXFLUXmX: You aren't in any position to tell anyone how they should voice their outrage, or which outrage is allowed and which one isn't, which outrage is "fair" etc.
No, but I can voice an opinion that I believe they're wrong. I can't ultimately tell anyone what they should or shouldn't get mad at (I could, but I wouldn't expect them to instantly listen or agree with me), but I can still believe that they're wrong or unreasonable to do so.
XmXFLUXmX: When enough people complain about something, generally, that means it's time for a change. GoG is getting a lot of negative feedback for a reason.
People can complain about a lot of things, but just because the masses complain about something doesn't mean they're right. In the case of the Fallout giveaway, GOG gave away a game that according to their statistics, a large majority of their user base didn't have (I myself didn't have it until fairly recently). That's a fact. From a subjective standpoint, I can understand why people would be disappointed (I was), but objectively, I can't see a reason why they've earned so much venom over that.
(Now, TheEnigmaticT's comments on pricing, I can understand...)