A while back there was Midwest Express Airlines. They were formed from the Kimberly Clark internal flight department, and was based in Milwaukee. They flew DC-9 and MD-80 planes with 2 X 2 seating, good legroom, good food, and baked on-board cookies.
The flights I took were only about $20 more than the competition. It was a great way to fly.
Then the internet came along and destroyed them. People will always choose the flight that comes out the cheapest, although there's a little leeway to pay more for a flight that doesn't leave at 4 AM.
Midwest couldn't compete, so they eventually went to standard seating and cut back on services. By then they were just like any other airline, except with a limited route structure that couldn't compete with the big airlines.
I rarely fly, but when I do I try to fly on Airbus narrow body planes, or Embraer regional jets. Those usually have 18 inch wide seats..