This is not a tool to for service providers to manage users for an SaaS offering, it's a tool for organizations to manage users for (ideally) the entire suite of SaaS offerings plus devices (including BYOD) used by the organization, across vendors, including internal apps.
Not really. Corporate identity management does much more around fine-grained access, automatic (de)provisioning, syncing data, device management, compliance and reporting, etc.
Of course it can also just authenticate users, but that's a tiny part of the functionality which is why it is so much more expensive.
