Imagine this -

You have a garden with ripe plants and seeds for future use. You have people to maintain and harvest your garden. However you don't have the tools to actually complete the harvest or plant new seeds.

I have the tools. I'm willing to lend you my tools but there are stipulations. If I lend you my tools, any vegetable I buy from your garden will have a reduced price and any vegetable you buy from my garden will have an increased price. I also need a specific amount of vegetables within a set time frame and you need to a pay a fee for using my tools. Additionally if you try to borrow someone else's tools I'll get very upset and the fee to use my tools and buy my vegetables will go up and I'll tell other people they should punish you as well and there might even be a penalty fee for trying to use someone else's tools.

Since you have the garden and the ripe plants and the seeds and the labour but I have the tools this is a fair deal.