I've never seen you mention the one reason most people I know have for buying/driving SUVs.
Safety.
These vehicles can withstand much more damage than passenger cars and the occupants are less likely to be injured in the event of collision. A close family friend explained it to me this way, "After that idiot plowed into my wifes car and sent her to the hospital for a month with 2 years of physical therapy after, I said to hell with fuel economy. She will never drive a small car again."
So it's not all just vanity. Many people are making a reasoned, thought out choice to protect their loved ones with the most massive (and therefore the most protective of passengers) vehicle they can afford.