Why does it seem like “losers” (using the quotes because I’m hating the term) are so much happier than careerists like me?

I’m a career guy who got really successful by learning how to code well. But I’m fucking miserable with my life. I don’t know what to do and I’m scared to lose my status and paycheck. It seems like the Walmart employees that I hang out with are MUCH happier than the career men I know, including myself. Is that actually true? Am I seeing this right? I’m pretty damn sad and I hate most things about my job except for the money.