I personally don't lash out at spammers or downvote them because it's a waist of my time and voting power. For me it's more cost effective to ignore them, that way they don't get a benefit.
However, allowing serial spammers and trolls to flourish has a negative impact on the value of the network. In some cases (not all) it is necessary to take action by using a downvote while being civil.
Fair enough:)
I agree