It's more about:

- Flexible scaling.

- Using other existing services from the cloud provider.

- Not needing to manage any hardware. (Or to hire someone to manage the hardware for you).

- Running your things in a data center. (Well connected, reasonable fault tolerant.)

- Less upfront operational cost (you are not required to pay for expensive hardware upfront).

For larger companies, especially such with massive amounts of micro-services it all about the flexible scaling and not needing to manage hardware.