“Sorry, but this is as plain as it gets.”
The passage you include is not an example of revenge in my opinion, but your passage doesn’t say what is done to the braves after they are hunted down.
Revenge is a form of punishment. Punishment is used in civilized societies. Guess it’s a matter of degree. Killing innocents is not acceptable by civilized people.
There’s the military logic that, for example, killing (sacrificing) ten people to save 100 is acceptable.
The braves were engaged in battle and killed, captured or run off. Frequently their village would be razed as well which often included deaths of non-combatants.
These attacks/revenge attacks continued until one or the other prevailed. There was also assimilation (as we also see in Israel) but overall the aggressive, dynamic borders group lost in the end.