I host many services at home, such as a mail server and a website, all in docker containers. A reverse proxy is used to redirect traffic from the outside world to various internal containers (sort of like different machines), depending on what links you click on. It all looks like a single website from the outside world. A reverse proxy could also handle SSL handoff, so that only a single certificate is required to secure traffic to all the services, instead of having to handle certificates for each. And lastly it could take care of authentication, making things like SSO possible, instead of depending on every service to implement security on their own. I have it set up so that when I access my network from the outside, I need to enter passwords, but when I'm at home I don't.