Welcome to the real world. The tyranny of the minority is a common theme these days. Fortunately, not typically so much at the gaming table though (although it does happen). Your example pretty much sucks and I would have told that guy what a butthead he was. You find jerks everywhere, sometimes even at the gaming table.
Tell your roommate to "Game on!".
I think that assumption (bias) is present in some posters, but not all.
But there are some posts - I've pointed to a few - which try to reply to those who obviously don't share that assumption from a premise of the truth of the assumption. Which is basically pointless: eg if someone is explaining how, as s/he approaches the game, the GM is first among equals for setting content creation, it is pointless to begin a reply to that person from the premise that the GM has unilateral power in setting creation!
What you describe in your example doesn't seem to me to have much to do with player "entitlement" vs GM "authority" at all. The GM wasn't trying to restrict things by way of exercise of her authority as GM: at least as you tell the story, she was motivated by mechanical rather than world-building considerations, mostly her inexperience with the PF mechanics.
As my 4e game reaches its conclusion, my group is gradually warming up to start a new game with a new system. It will be our first time playing this system together, and I have expressly said that, because of our relative inexperience, I woud like to keep PC builds fairly vanilla.
To be honest, for me there is a degree of tension between (i) "K" being a friend of your GMing friend, and (ii) "K" wrecking your GMing friend's game. "K" doesn't seem like a particularly good friend, if he's trying to bully your friend into doing something she sincerely doesn't believe she is qualified to do.
But to my mind, at least, this is not very analogous to a GM saying "No tieflings because in my world civilised folk kill them on sight".
I have noticed a lot more me me me type players in the last 15 years then I used to see. But then I see a lot more of this everywhere. The whole my rights come first instead of my rights stop where your rights start.
I feel that it is up to everybody players and DM alike to make the game fun for everyone at the table. And sometimes that means not getting exactly what you want. Sometimes it means stepping back and letting another player have the glory or letting the DM have some fun too.
Like I said my fun as a DM is to build worlds that make players want to come and explore and not feel that they have done this a dozens time before. A lot of us have been playing since the 70s and the same old vanilla game world is dull. I got burned out on haughty elves, Scottish dwarves, half orcs with angst. So when I built my world I tried something different. And so far most of the players who played in it really loved it.
I think making thematic choices in world building is also a for of DM authority unless your group does shred world building which i have rarely seen in my 40 something years of playing. Players may add elements with their characters but for the most part the actual building of the world was left to the DMs.
In my homebrew tieflings would be killed on sight. They are hated they served as the shock troops for Tiamat and her demon and devil generals. They killed, raped, tortured their way across the countryside. They showed no mercy. The ones that did not get off world before all the passageways between worlds closed were hunted down and killed. It would be very hard to play a tiefling and not get yourself and the party killed. As the DM I have made this choice, and this was before 4E anyway and they were not a core class, and I think the players should accept it they after all agreed to it upfront it was not a surprise.
I personally am not fond of kitchen sink setting as a player or a DM I prefer a world that is more defined. I will play a kitchen sink world but I am not sure I would DM one. Hussar said he tried Planescape and it wasnot to his liking so no one would bat an eye if as a player he says I won't play in a Planescape world. But if a DM says things like this then it seems it gets judged differently. Karinsdad has said he does not want dragonborn in his game because they are monsters in his world and some people seem to think he is wrong for doing that. We all have our dislikes and the DM should be allowed to have some too. As long as the DM is upfront about it then the players need to decide play or not. But he is not a bad DM for doing it.
In our group we have different DMs and players for the most part know what we will DM. My games tend to be heavy on political intrigue, heroic deeds, a lot of gray not much black and white. I have no desire to run a game for a bunch of morally corrupt PCs or a hack and slash dungeon crawl. Another DM tends to run your traditional DnD sandbox he allows a lot of splatbooks the world is black and white, he lets the powergamers powergame to their hearts content. His games generally last around six months and is the perfect game to try out new classes and races. My roommate runs adventure paths and modules. We have a Shadowrun DM and a Hero System DM.
And for the most part we know what we are getting into as players. There is already an implied social contract in place if you say yes to a DM game.
K is outside of gaming a decent fellow and a supportive and loyal friend. In gaming he can be a pain because he can be set in his ways and just can't seem to grasp it is just a game.
). Players should be helping new DMs, not hindering them. JMO.
