To be honest, most are living very comfortably with mom and dad. Workers at or below federal minimum make up about 3.3% of hourly workers (makes you wonder what all the fuss is about) and half of minimum wage workers are under 25 https://www.bls.gov/opub/reports/minimum-wage/2015/home.htm " Among employed teenagers (ages 16 to 19) paid by the hour, about 11 percent earned the minimum wage or less, compared with about 2 percent of workers age 25 and older"  So this isn't a statistical outrage even among teenagers.

Another tidbit from that link "About 7 percent of part-time workers (those who usually work fewer than 35 hours per week) were paid at or below the federal minimum wage, compared with about 2 percent of full-time workers."  So this lengthy article is about, specifically, 2% of full time workers.

Note all these numbers are 2 years old.  No one would argue that employment is worse now than in 2015.