I see the cloud mostly for startup-ish companies hoping to grow rapidly but which want to avoid large upfront expenses to be ready for said growth.

A stable company where growth as a percentage isn't likely to be significant can run things cheaper on their own in most cases. At least if you consider the cost of the inevitable departure from the cloud provider either to switch another or to go on-prem. And if you aren't willing to make that exit, you can guarantee your cloud provider won't stop cranking up the fees until the threat of you leaving surfaces.