The amount invested in the company is provided by each separate investor, but those investors do not then negotiate separate deals with each worker. The investors “collude” together to creat the business and have greater negotiating power than they would on their own.

A union is merely the labor version of joining together to increase leverage and is not any special level of collusion greater than the investors is what I am getting at

And yes saying the workers are colluding because they are working on the same car is what’s happening if you are going to call banding together to negotiate rates is colluding. There is non union labor and other unions