Preventing suffering is what I care about, and I'm going to try to convince other people to care about it. One way to do that is to invent plausible thought experiments / intuition pumps for why it matters so much. If I do, that might help with evangelism, but it's not the (original) reason why I care about it. I care about it because of experience with suffering in my own life, feeling strong empathy when seeing it in others, and feeling that preventing suffering is overridingly important due to various other factors in my development.