No individual has any right to make a living doing anything they want to. If sufficient people are willing to do a job at a reduced wage because they enjoy it, that is their right.
This is like saying that libraries should ban unpaid volunteers in order to justify the hiring of more librarians.
It is illegal in the US to have volunteers do work that would otherwise be done by a paid employee. That's why unpaid internships are, by default, illegal - to be legal they must replace the payment with school credit and valuable experience, basically.
Labour laws set minimum standards that all companies and employees / contractors / whatever should adhere to, because it reduces the likelihood of abuse.
The "right" you mention doesn't exist in e.g. countries with minimum wage laws.
This is like saying that libraries should ban unpaid volunteers in order to justify the hiring of more librarians.