Marketing for Keychain is marketing Hive. Like a payment app ( Paypal and so on)

That's the most neutral way for hive marketing, and it could be paid with recommended dapp inside ( for example splinterlands, peaked and so on).

Hive alone with keys is the very unlikely average user will use many different dapps. With keychain it is unlikely only use one :)

Also marketing could paid by DAO because its 100% neutral and the "recommended" area could be paid to DAO fund for example :)