I suspect some truck owners feel the need for a macho boost subconciously. Most don't get enough exercize and enjoy the sense of flexing some muscle even if only with their vehicle; humorous, but true.
But, it's also a cultural affect in some areas. Young folks (male & female) who have grown in families owning livestock want their own truck, then their own horse-trailer. In the material world (so Madonna tells me) people want the nicest goods they can own, ergo, the Cowboy Cadillacs.
Many construction workers own trucks by necessity, which is my story.
I guess I'm an exception. Since I spend a lot of time in my truck (125,000 miles in barely three years) I afford myself the luxury: Bose sound system (music is important to me), heated leather seats, climate-control, voice-activated phone system, etc. I drive in excess of fifty miles of dirt road every day of work and a total of 125 miles (min) every day of work. I buy eight all-terrain 10-ply tires every year. I chain up the front wheels at least twenty times each winter and all four wheels at least six times. I've lived eleven miles from payment for over twenty-three years. They made those fancy trucks just for me.
Besides, I have a very small penis.