[G&K] City-States: Turning them off?

I've always played with whatever amount of City-States the map size defaulted to, but I've grown a bit weary of them for some reason I can't quite pinpoint. Has anyone played a game without them, or with just a few of them on a large or huge map? Does it throw things way off if you do so? Come to think of it, I don't even know if you're able to play without any. I haven't fudged with that slider. Would it be a shame if I played my next game without them?

Currently on G&K but likely to start playing BNW next game.