It's made for administrating dedicated servers, where the host does not actively participate in the game. This has several major advantages.
* Performance: The server does not need to render the UI, and is often completely headless (hence the use of this software).
* Fairness: The host in your scenario has zero latency, giving them a competitive advantage over players with tens or hundreds of milliseconds of network delay.
* Availability: Some games provide a persistent world with the ability to drop in and out at any time (e.g. Minecraft). No single player is present for the entire session.
* Performance: The server does not need to render the UI, and is often completely headless (hence the use of this software).
* Fairness: The host in your scenario has zero latency, giving them a competitive advantage over players with tens or hundreds of milliseconds of network delay.
* Availability: Some games provide a persistent world with the ability to drop in and out at any time (e.g. Minecraft). No single player is present for the entire session.