No, but it's a likely requirement of a nontrivial app. You can emulate it on AWS if you're using something like backbone, but only for public content.

Thats correct, often times most people don't even set page cache times in their dynamic content.

I think it's because most web developers don't ever have to understand how this stuff works. It's sometimes easier to just throw hardware at a problem than engineer it better. However, understanding what you can do is key imho.

Isn't the point that dynamic content is changing and you don't want to cache it? What would be a good cache time for HN for instance?