They did...
They're literally just passing on the costs https://platform.claude.com/docs/en/about-claude/pricing
Anthropic just provides a subscription - which Enterprise usually doesn't want you to use because everything you're submitting through that will be trained on / becomes part of their model.
So If you use it without explicit permission from your employer you may be committing a contract violation which can have serious consequences - up to jail time - as they can sue you for that.