Displaying themselves in public can be job enough regardless of money. That must be one of the biggest motivations.
I used to go to the far extreme of the opposite direction, wearing the same thing for six months straight, never applying lotion, cream, gel, wax, or whatever, not on hands, not on face, not on hair. I changed somewhat in the recent years. I use at least shampoo for hair, and had a minor surgery this year, the first time I ever went out to see a doctor for myself on my own since birth.
A fast-growing number of young people in South Korea seem to think it's liberal and sophisticated to have tatoo and piercing. Some of them must believe they are signs of advanced and highly evolved forms of intelligent beings.