The technologies are not just for large deployments IMO, it's the next logical step of leveraging OSS software: composition at the service layer instead of binary interfaces. You can pull down an ElasticSearch image, for instance, to provide search for your application, and write against their REST API. It then gets rolled into an orchestration with your app. You can debug locally against the rest of the orchestration, then package the whole thing using a script and/or some config files and deploy it to a stand-alone server, the cloud, whatever. Set it up once and deploy anywhere without (too much) extra hassle.

What Amazon has done is take these workflows and make them very developer friendly. You can save some time and energy (and money) using EKS over managing your own kubernetes nodes on EC2, for example. Or you can use their native services that provide other niceties. Welcome to the latest form of vendor lock-in!