That used to be the role a union played as well. Before unions got all corrupt and self-serving, there used to be a better than market guarantee of quality and

That used to be the role a union played as well. Before unions got all corrupt and self-serving, there used to be a better than market guarantee of quality and conduct when hiring union labor. Unions would train and discipline their members to meet the standards promised to the employer. That's why they were able to command better pay and benefits.