I am too lazy to be vindictive. Well, I'm being a little harsh on myself- I'm too laid back, I'm just not very bothered by things. When I was a kid I was very stubborn and held a lot of grudges, but I've grown up, had a few really shitty things happen to me, and now these petty things just seem really insignificant. Holding onto a grudge is hard, it takes serious mental effort for me to keep one up for very long.
It sounds incredibly stupid to my cynical mind, but you're just bringing more hate into the world and that's pretty un-Dude. I thoroughly believe that the world would be a much better place if people were a bit more fucking chilled and forgiving, not out of anything to do with love, but because it's just a damned load more practical. Vindictiveness doesn't erase the original problem, it just draws it out for far longer than it needs to be. Getting 'even' doesn't make the slightest bit of fucking difference to your life, it just makes their life worse. I find the idea of getting joy out of that pretty sick to be honest.