OK, but the idea is the same. You could have the big corporation pay the employed person X and the car insurance company Y. Or you could have the big company pa

OK, but the idea is the same. You could have the big corporation pay the employed person X and the car insurance company Y. Or you could have the big company pay the self-employed person X+Y, and self-employed person pays the car insurance company Y. If the big company is not willing to pay X+Y to the self-employed guy, they won't be willing to spend X+Y on an employee. The only difference is if the big company can get better rates on the relevant goods than a self-employed guy.