I wasn't with the company when it started using Stripe, but there's really no need to interact with Stripe besides setting up your account and using the API they provide. Since being involved with Stripe, I don't we need to talk to them more than once a year on a "so, all good?" type of emails.

They basically made it so easy to use them that it doesn't cost them anything to add small companies.

They can't afford it because they have no customers, because they turn down small customers and then Stripe already has them when they become big enough for Adyen.