More details on the folks that saved the seats
It was not truly apparent upon boarding, but I will share what I think happened. When I boarded as A52, I saw row 1 ABC and DEF filled (well, DEF had 2 people but one looked like a gentleman of size, so giving him the benefit of the doubt that he purchased a second seat). I observed folks seated in row 2 ABC passing things back and forth with row 1, and there were interactions with row 3. Row 3 ABC was where bags were left. What I can surmise from this, is that ~4 members of the family pre-boarded, and saved seats for the remainder of the family. This took up 12 seats in the first 3 rows.
I think Susan said it best: