The cloud trades agility for cost.
We're a small company that used to have a full rack in a colo, and have completely migrated to AWS 6 years ago. Our cloud costs are ~20x what our colo cost was.
There are things we use in the cloud (DynamoDB, Aurora, CDN, etc.) that I just don't want to have to build and manage on my own. For us, the managed services are very much worth the extra cost.
I couldn't believe how much better life is without having to diagnose failed DB backups.
Very true.
Did you actually need a globally distributed CDN just for 15 minutes though, or was this a learning/PoC exercise?
For any business that has very spiky resource needs (such as this example), the cloud is ideal.
I've never been in such a business though, usually there is a fairly predictable (hopefully growing) steady load with small variance.