Thank you. Actually this makes sense a lot of sense.
I would describe it as follows (and please correct me if I am wrong):
A = Website Owner, B = Vendor
1. A allows B to set-up shop on site and sell products
2. A can choose to become a commission receiver or payer. How? Just by making the commission payable percentage for example – 95% then this means A is just charging 5% for any product B sells. Alternatively, by just applying a 5% commission rate in the WPVendors Setting, A agrees to pay away only commission to B