Paul Palmer...
You're definitely entitled to your opinion...
but here's how I see it.
When you're paying for a domestic US flight yourself, and you aren't using an upgrade to 1st for whatever reason, you want to take full advantage of the perks of elite status.
That usually means "gimme the good seats up front!"
From Joe Q. Vacationer with his seven screaming children to Jane S. Business with her projection equipment in seven carry-on bags, space above AND below is at a premium. The trend I saw first a few years ago was to stuff carry-ons (which should probably have been checked anyway) in one of the first two overhead compartments and keep walking to one's seat in 39E!
That reduces the value of the seats near the bulkhead at the "class border."
In short, if I were to wait until everyone else has boarded, as I refuse to do, I would be one of those poor souls who has no place to put his bags...
No thanks! I'll leave that for the latecomers.
My partner flies weekly on the ORD-LGA route, which no matter what time of day, seems to be prone to silly delays and screwups... to add insult to injury, the latest trend is to skip preboarding for elites. It is unacceptable, IMHO.
And I cannot accept the excuse that everyone on the flight is elite, so no preboard! Again, this is a class system... so start with First, then Explat, then plat, then gold... hell, it's their system that gave out so many credentials in the first place!
Whew... okay, I'm better now.