To answer the age-old question...
Q. If three people are sitting in a full row on the plane, who gets the middle armrests?
A. The person in the middle. Why? Because the person in the window gets to lean their head on the window, and the person on the aisle gets the aisle armrest and to lean out into the aisle* every so often. The sucker in the middle gets nothing but the solace of leaning their elbows on the two middle armrests to ward off the fat spillover of two complete strangers.
(*But please, not when the beverage cart is in the aisle)
Yes, I have had to have this discussion with passengers on board. And yes, they were all (outwardly at least) adults.
If you have any other airline "mysteries" you'd like solved, leave a question in the comments!
Image: Prop airline chairs from the tv series "LOST"- from Google Images