More specifically, why do you care what THOSE people think? They obviously look down on you for your skill at a difficult video game and nothing is likely to change that; they're even willing to be hypocritical to do so. Don't worry too much about their thoughts on DF.
I assume they're the types of people who decide to wear thick glasses for the hell of it, or be a fan of The Big Bang Theory, and call themselves nerds, or own a copy of Angry Birds (or any other game that comes with their latest iPhone), and call themselves gaming nerds (whereas they don't even know what E3 is, and calls it lame; or thinks Macs are gaming computers), and their scores don't even show the slightest effort in improving their score or something since their first attempt.
I suggest, come Christmas time, you gift them with a Rubik's cube, scrambled, and on the card, tell them that half the fun of them is in solving them, or learning how to solve them. Consider it a physical representation of the fun behind DF. After you scale that learning cliff, you can really start having fun with them; much like the Rubik's Cube, being able to know them so well, you can make pixel art out of them, just by legitimately rotating them to your specifications.
If they fail at getting the hint, mail them a copy of Twilight (or whatever book they seem to be a "die hard fan" of), except inside it, it's in another language they don't know (even better, make it in phonetics, like Chinese or Japanese). Scale the learning cliff of learning another language besides good English and Social Media/Bad English. I mean, they gotta learn something sometime, why not? I mean, I regret suggesting Twilight, but it's something they'll accept; however, not being in the same language, that's something else that at least makes the book seem smarter.
If everything is easy, then life would be boring, and we'd all be lazier than we already/usually are.
Alternatively, if you want to be more merciful, give them a copy of Rollercoaster Tycoon, and see how far they can get. How dare they put down creating your very own theme park from the ground-up. I mean, it's a fun and challenging game, and with enough know-how here and there (understanding the physics of certain rides, keeping everyone alive and happy, some simple economics, etc.), you can swim in money like Scrooge McDuck, and have some pretty kickass rides all over the place before you reach the goal. Hell, even Tropico would be another good game to get them to play. Teach them the difficulties of running your own island nation. Will you focus on living conditions for your community, or enslave them on pure capitalism, for tourism, while the citizens continue living in shacks? Oh yeah, and they have to understand how politics works. Especially good for these political seasons to let them know that not all demands can be met, and you can't always be benevolent all the time, otherwise, your economy can crash and burn fast.
I would really lose my faith in them if they put down fun games like those because "OMG your such a nrd.". I think I felt carpal tunnel symptoms form while typing that; not to mention, my grammar sense is cramping up just reading it. If they don't want to play games that require a few synapses to fire, then give them a pet rock to play fetch with. It's a gift befitting of their intelligence and willingness level.
EDIT:
Oh wait, I just thought up a good counter on their accusations of nerddom, and their hatred of nerds, while unintentionally being nerds themselves.
Do they filter through their equipment when they play BL and BL2 and adapt their equipment to best take down a group of enemies quickly or to achievement hoard (similar can be stated of the Fallout games; Even with BL2 and Cult of The Vault symbol hunting)? Are they reliable snipers even without zooming, or know the trajectories of grenade physics when clearing out a room? If that's the case, then hey, guess what? You're using critical thinking (a dominant trait of actual nerds and... well people who think)!!!! Here's a gold star (or a banana sticker), oh, and admit it, if you actually use math to figure out the best weapon (sometimes the seemingly weaker ones are far better), then you're closing in on being a nerd; face it, you, like the rest of us, are a little bit of a thing you hate to be, or aim not being
(I'm sorta going off the Ron White bit on how we're all "a little bit gay", and how he called a homphobic person he knew, out on it, using porn as an example).
EDIT EDIT:
On the FPS game front, you can also always
show them this. If you're a real gamer, you'd play Doom more/again.
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