I'm unfamiliar with that delivery uniform, maybe it's another country's postal service, but the USPS has had a kind of "higher purpose" associated with it. E.g.
The Postal Service shall have as its basic function the obligation to provide postal services to bind the Nation together through the personal, educational, literary, and business correspondence of the people. It shall provide prompt, reliable, and efficient services to patrons in all areas and shall render postal services to all communities.
Neither snow nor rain nor heat nor gloom of night stays these couriers from the swift completion of their appointed rounds.
Worked manual jobs (assembly line) right out of highschool (well fast food during highschool too), and absolutely hated how boring it was to me. I'm not a social person, and used to have really bad social anxiety. I've always had an interest in computers, for whatever reason, so after a few years of manual labor, decided to go to college for that. Also, I lived in a very depressed area, and the jobs I had were very low paying, to the point I couldn't afford to move out from my parents, so something had to change.
Anyways, I made the right choice, because I'm pretty good at what I do, and I love encountering and solving difficult problems.
While in college, I did work at a metal fab shop for a summer, and I could've totally seen myself doing that as well. It wasn't mind-numbing like assembly line work, did involve problem solving, and the tools and machines were "cool."