The difference is, Google is the only company that is both trying to sell cloud services, and giving their product away to their competitors.

The company I work for uses multiple cloud providers, but does not use GCE. They don't even think about it. I think the reason is a lack of confidence, along with other business and technical reasons. Google just isn't a serious company when it comes to supporting large businesses. Like it or not, that old adage about never getting fired for buying IBM is still true.