It's only "anti-market" if you fall into the common fallacy of conflating ideas of individual and economic freedom with the functioning of the markets. It's not at all the case that increasing say contractual freedom is always coincident with the improved functioning of the markets. The classic example is anti-trust law. Laws banning producers from forming cartels to fix prices is a restriction on contractual freedom, but they're a restriction that produces better, more competitive markets.

There are a lot of considerations on the elasticity of demand for labor, information asymmetries between employer and employee, relative bargaining leverage, etc, that weigh in favor of laws to regulate the labor market. I think a great example is bans on NDA's or non-competes. They help make the labor market more liquid and prevent anti-competitive labor practices, even though they are a restriction on contractual freedom.