No they shouldn't. There are plenty of jobs out there which simply aren't necessary and would just be eliminated if required to pay a living wage. Baggers at the grocery store or greeters at Walmart for example. Those jobs provide enough benefit to customers and the stores that they're worth $8/hr. But if required to pay those people a living wage, the stores would just eliminate those positions because they aren't essential.
It's okay for there to be jobs that are intended solely for retired people or high school kids to make a little money at, but not to support a family.