Earlier quoted context omitted.
Why do you care about boarding priority? The plane leaves at the same time for all passengers. All you do is exchange maybe 5 minutes on a seat outside the plane for 5 more minutes inside the plane.
Carry-on luggage for one thing. (And the luggage I take is comfortably within limits before you ask. I'm also frequently in a bulkhead seat so the luggage has to go overhead.) I also like to just get settled in.
Often the people handling the luggage think I'm strange to pay $50 to check a bag when I haven't maximized my carry-on bags or even take advantage of the free bag I get because I have the credit card. It might even get me investigated by the TSA for being un-American.