I'm eating animals. YOLO.
You could also claim that you want to steal cars because you only live once and you're not going to NOT have driven a Porsche during your life. Or NOT having eating human flesh. etc. This is not a great argument in any other context, so there's no reason to give it a pass here.
Carnism is fundamentally based on granting special rights to special species. Again, this argument doesn't actually prove a justification for this special pleading. It just skirts the issue