It might be the best approach is to offer a commercial license alongside the open source one, in a subscription model. It's just what fits into the preconceptio

It might be the best approach is to offer a commercial license alongside the open source one, in a subscription model. It's just what fits into the preconceptions of a business. They get an invoice, they get a something in return, case closed. There's probably not even a need for extra support. Only thing necessary is some viable way to pay them. Then there's no need of developers talking to managers about justice, how things should be, and all this fruitless stuff. It really doesn't matter that you could obtain it legally and for free, often times.