If rights vendors sell sponsorships for a third party, they usually charge a sales commission. As an example: If a rights vendor charges a 20% provision, they would get 200€ out of a 1.000€ sponsorship. The rights vendors use the provision to pay for the sales team that sells the sponsorship assets.
A usual commission in the sports industry would be in the range of 20-40%. In some instances, vendors charge commissions of 70% or more, especially in sports with a high management effort, like boxing.
Sponsoo charges a provision of 20%, but doesn't even demand exclusivity in return. This makes Sponsoo one of the most price-effective agencies in the market.