[Tautologistics]

That is the short sighted view though. If everyone always turns the other cheek then there is little consequence to hurting or screwing others, which then reinforces the wrong-doers behaviors and perhaps even encourages others to join in. Within reason, one should always make it clear that certain actions are simply not acceptable and that there are clear consequences for those actions. If not for your self, it may save someone else from that same injustice.

The long term results of action vs. inaction will always have an impact on society as a whole and on one's personal quality of life; it just might not immediately noticeable.

If however, one is driven solely by revenge then it might cause one to expend way too many resources or cause one to take things too far but, still, intention has little effect on the external impact of an action.

[marciovm123]

This is referred to in behavioral economics as the "second-order free-rider problem", and is an active area of research, e.g. http://www.cirano.qc.ca/ee/ESA2005/papers/Kiyonari.pdf