They don’t care because they will be dead before they ever see the effects of their selfishness. They will literally never have any consequence.

I’m sure they know in their hearts that they’re descendants will suffer and die because of what they do today, but they don’t plan on ever feeling bad about that because they will have already died safe, warm and comfortable in their beds, surrounded by their loving families, after a lifetime of luxuries. Everything to gain and nothing to lose. Why not fuck the planet?