Any job between 0 and minimum wage becomes either a 1099 job or a black market job. When people say $25 minimum wage, they really mean make sure anyone paid less is on the black market and has no protections.

There are instances in which people pay to work --- "finders' fees", "placement", various assessments to supply tools, (mandatory) uniforms, station rental, etc. Involuntary servitude still exists, even in advanced countries, though it is illegal, usually as "white slavery", mostly immigrant sex workers.

$0 is not the lower limit.