Some people seem to think the federal minimum wage of $7.25/hour (resp. $290/week or $1200/month) is way too high and should not exist.
I'm not even sure if it's enough. Can anyone cover their basic needs such as food, rent, gas or public transportation and other essential needs, let alone have something left to pay for unforeseen medical bills or further education? Are hobbies and visiting family and friends during holidays a privilege in a "first world country"? Should it be a privilege anywhere in the world?
Could you live with being paid that wage (if you can't stay with your parents rent-free and other perks that people get without seeing it as such?) until you retire?
If your answer is "those jobs aren't supposed to be full-time jobs, but rather something you do as a teenager or a student who then have less time for sleep or studying to get good grades to get a well-paying job", then you're basically saying, that it's okay to exploit poor young people who -unlike the rich kids- can't afford not to work while studying and don't have daddy's connections to work part-time in a nice office with a better salary.
If your answer is "those jobs shouldn't even exist, because customers can do it themselves", then you overestimate the willingness of "some" customers to be decent in exchange for lower prices in food or clothing or anything really.
If you think your time is too valuable for menial tasks like these, realise that someone has to clean the mess others (not you, of course) leave behind for the next customers. These jobs exist for a reason, and they have value.
People who do these jobs don't deserve a bleak life for doing tasks that many think are beneath them. They give up 40 hours of their lives every week for work too.
People don't just need a job to not feel worthless.
People need a job that gives them the dignity of being able to fully support themselves without the help of their parents or the government to not feel worthless.