Certainly a portion of carry-on travelers do so because of the reasons you listed, but the rise of checked baggage fees unquestionably made matters worse. I've

Certainly a portion of carry-on travelers do so because of the reasons you listed, but the rise of checked baggage fees unquestionably made matters worse. I've been traveling for business since around 1999. Not a terribly long time, but long enough that I remember the days of simple metal detectors at security checkpoints and family greeting me at the gate when I landed. Overhead space was rarely a concern except for commuter-heavy routes. These days, I rarely get on a flight where some passengers have to gate check. The "overhead bin space is going to be tight" announcement has become a standard part of many flight attendant's duties.