For those who dismiss concerns about MPG, it's an insidious thing that can creep up on you.
Right now fuel prices are relatively low (historically speaking) at least in most of the US. But it doesn't take much of a "spike" in prices and all of a sudden it's costing north of $100 or more to fill the tank. On a long trip, that's a significant chunk of your budget getting burned up in the engine and blown out the tail pipe.
Last time we had a quick spike in fuel prices (circa 2007 - 2008 or so IIRC) I was on a few message boards and people with gas hog vehicles were hurting big time: "I can't afford to drive this pig" "This thing is killing me with fuel costs" "I've got to get out of this gas hog" etc.
I've seen people who follow the "who cares about MPG?" advice (which is common on forums like this), spend a buttload of money building up a 100 series LC or big pickup or Wrangler...and then a year or two later, sheepishly admit that they can't afford to drive it anywhere as they put it up for sale to buy a 4runner, Tacoma or similar vehicle (or even better yet, to see them admit that they drive their Subaru more frequently because they don't really NEED the capability of the big truck and the money they save on fuel by driving the small car more than makes up for the lost capabilities of the big rig.)
So it's not a trivial concern, unless you're independently wealthy (which I assume most of us are not.)