I think they meant that the business model of a hitman specifically, because of, y'know, the killing. So, the reductio would be demonstrating that the "who pay

I think they meant that the business model of a hitman specifically, because of, y'know, the killing. So, the reductio would be demonstrating that the "who pays isn't the same as who 'receives' the thing" isn't a sufficient defense in every case.