This is a great point. I know that I've certainly been an absolute selfish asshole in my life at times when I should have been compassionate, caring, and understanding. I believe that sometimes the supreme being (or whatever theory of randomly assimilated matter from absolute nothingness you subscribe to) puts people in your path that you can help and there is tremendous weeping in heaven when that vulnerability is used for selfish reasons.

I will say that "the check" certainly came for me to pay later when I matured some (as I believe it eventually does for everyone), and I relive painful moments (for the other person) that I caused, and frequently wish I could go back and make different decisions. I've even gone so far as to reach out to people in the present to apologize for the past- sometimes they're receptive, other times they're like "Fuck off, asshole." I completely accepted and understood the latter responses.