Sync for Lemmy

Sync is a for profit app. Why would the dev not have the right to advertise the one other app he is developing? And in order for the user to become interested, he has to sell the idea of Lemmy first if we are talking about new users. If we talk about old Lemmy users, then he should be advertising his app on Lemmy itself which he is already doing by setting up a community and posting to other relevant ones.