Sheeple. . .etc
Why stand in line to board first?
1. Early boarders have a better choice of overhead bins. A bad leftover can cause a missed connection. Only had one really near miss, but I had a "favorable" bin and made my connection, abeit a bit out of breath.
2. It is much more comforatable boarding the relatively non-crowded aisles at the beginning of the boarding process. Note that my frequent flyer status rewards me by allowing me to board early, right after premium class.