Sacred Haven of Debauchery

Come on. Even in most strategy games, you need to defend and capture. In RPGs, there are also killings, but they are still more interesting than shooters because, in addition to combat, they have a role-playing element and much more.

In RPGs, killings are a tribute to the setting because most of them are "Heroic Fantasy."
In hack-and-slash games, killing is the main goal; the point is to... kill monsters, collect items, become stronger to kill even stronger monsters, and... well, you get the idea.