People like to grumble about the bygone era of generous seats, lots of legroom, amazing catering, and people dressing up for the occasion as if they were going to the opera. These are understandable sentiments, but the truth is, the bygone era didn’t have lie-flat seats. And it wasn’t even possible back then to redeem a ticket for miles, considering that modern frequent-flyer programs only date back to the 80s.