I had two empty seats in middle aisle recently, I knew it was too much to hope. Sure enough a family laden with bags of fast food boarded at the last minute, displacing the guy at the opposite end of the aisle with barely a please or thank you. The airlines cannot physically cram anyone else on board at this point, unless they start taking space from business & first class, who would not stand for the indignity heaped upon the wretched masses.