But. It shouldn't be free. It's an addition that adds a sizable chuck of a game for a fraction of the price of a new game. There would be no reason for it to exist if people didn't pay for it. It's not worth any company to make something on that scale with that much dev time just to give it out for free.
No one is saying you have to buy DLC. But I think your reasoning for not is completely irrational, especially when it comes to something like Civilization who does DLC so well. It's not a cosmetic change, it completely revamps the game itself turning it into something new.
Side note. I didn't even know BNW was considered DLC, I thought it was an expansion pack.
I understand the flip side, I just don't agree with it.
I know that devs shouldn't feel obligated to make free DLC, and that's their decision.
But I won't ever buy it. Because I feel I've already purchased it. I just want to try too many different things to restrict myself to buying something to expand a world. I am already involved in immersive, expansive worlds.
I'm at the stage where I want to see multiple different stories, not variations or rehashes. Civ V is a great game for example. But at some point, I want to try something new, like say, Prison Architect, or Skyrim, or Papers Please. I want to experience that new world. Something COMPLETELY different from what I'm already experiencing.
It's counter productive for me to buy in to something I've more or less experienced, even if it is an upgrade over the vanilla game.