They have paid subscriptions and it gets you using other Meta services more so they make money from ads. If that's not enough they might put ads and affiliate links when you use it for shopping.

The VM is about the same specs as a 9EUR/month VPS from Hetzner but it only runs a fraction of the time, they spin it down when Muse stops using it. Meta is a hyperscaler with optimized infra and they don't need to make a profit because VMs are not their actual service. I think it costs them at least 10x less than inference for most users.

Hyperion.