Overspending in general is typically due to feelings of entitlement.
"I deserve it." (the classic)
"I grew up with very little as a child so I'm gonna get it now as an adult."
"When I was a kid my parents couldn't afford to give us Christmas gifts so I'm gonna buy that car to honor them."
"My great-great-great grandfather was enslaved on a cotton plantation so I deserve that new car today."
Someone else already mentioned it, but really it's the illusion of wealth that people seek and not the wealth itself. Attaining the wealth requires the development of skills via education and plain ole hardwork....illusionites only desire materialism and a fleeting lifestyle and would only break a sweat to attain that next item that gives the appearance of money. I know folks that will only wear, drive and live in the best regardless of income levels or debt.....if it doesn't have a label they ain't gonna buy it. These men and women are the types that would happily spend $150 on a designer shirt. Me, I'd rather spend $25 on a shirt and make it look like a million bucks, but I still believe in a presentable, professional wardrobe because the great unwashed masses are shallow-minded delusionites and need that fashion statement for the sake of security in doing business (actual credentials be damned LOL).
I have a running joke that in most big corporations the hourly wage collectors and clerks wear more expensive clothes and drive more expensive cars than the majority of executive leadership.....I've seen this at every place I've worked.