I call them casual gamers. They're not really interested in the breath of games the industry has to offer & their consumption habits are very limited (casual consumers?).

I'm sure there's a better term but this is what I use. To clarify I think this actually represents a large portion of gamers and I don't see it as a bad thing, but its in stark contrast to audience that is avidly watching E3 for the next game they're going to get excited about, or the kind who picks up a title because its on sales or because they've heard good word of mouth, the kind who is frequently navigating reviews and gaming media to find their next purchase. New games and Ips often rely on this latter audience to gain some traction and footing.

In the mobile market there is a term called "Wales" but thats for people who spend a large amount of microtransactions on one game. I think the same can apply to many FTP games on PC or console. 

I can relate. I played
Starcraft:Brood War from 1998-2002
Warcraft 3:Frozen Throne from 2002-2010

The competing was the essence for me, I did play other games at LANs or some casual games at console but for the absolute most part I played to win in those games.. at that point in my life getting really really good at a specific game was definitely more rewarding than beating a dozen or so games a year like I do now.

This

Fans/actual core gamers.
Why would they be casual when they spend 1-x hours a day on a game?

Of course, they are all casual and boring, idiots, time wasters or having a low IQ because they are not like "you" which makes them worse by definition. ;)

Yeah most people I know who play games tend to just play 3 or 4 games. Buy the new FIFA and COD each year sorta thing.
What to call them? I dunno, people who're missing out?

I know what you're saying. I feel like whenever I look on kijiji to see what people are selling, everyone owns the same games (AC, COD, or annually released sports titles)

Where does casual mean "worse"? And I know tons of people who use to pour hours upon hours into Candy Crush, Sims etc, so I've personally never looked at it context of how much time you spend on a game, but thats just me. These are just loose semantics, I far as I'm aware there is no true definition.

Boring people.

Idiots.

Lately I've been playing nothing but Age of Empires 2 online, Battlefront and the new Battlefield of course. And I feel like an unsophisticated idiot because I'm not paying attention to all these fantastic single player games I planned to play.

I've been that way for a bunch of years. Almost exclusively played one game, Halo Wars, for years now. And as of this writing it's a 7.5 year old game! I've been playing it since launch, and before that I was playing the crap out of its demo. However, back in the day I played a lot of things, including PGR. Thanks to Games With Gold I recently discovered how awesome Forza Horizon is, and how it's the true successor to PGR, so I'm expanding my (ahem) horizons again.