Events company (HeadBox) wants to take 10% from deposit for themselves… Should I accept this?

I own an activity venue / restaurant and have been contacted by a company called HeadBox which finds event venues for clients.

They’ve ‘chosen’ us as their preferred spot for a small event (14 people) for a work party from a major energy company, but while drawing up the invoice on the event deposit, the HeadBox event planner said they take 10% from the payment as their fee. For the hospitality sector that 10% is a lot for us so I’m very hesitant to move forwards on this basis. It also feels incredibly cheeky and they should be getting the payment from their client, not us.

But they’ve hinted at bringing more business our way and asked to set up a credit account. But I don’t know if this is simply a tactic to get us to go with them.

Has anyone used this company or similar before? If it’ll bring us a ton more events I’d be willing to try it but very hesitant right now.