I suspect I won't know any more on the day I do go to that big fishbowl in the sky, but hopefully I'll have gotten to eat a lot of really excellent algae and swim through some cool castles. With the sunken chests that open and close, and the lights and skeletons and everything!
My point is that there's very little we do that needs to be done. You need to sleep, shit, and eat. Beyond that isn't really any of your business, but it can be fun. Pissing all over someone else for doing something you don't personally approve of is MORE pointless than how pointless you think what they're doing is!
So is taking offense to someone doing so. They're not the ones buying the fish-flakes, it doesn't matter what they think of you. Remember that it's a game, and remember what games are for. EVEN if there is no higher power, and this is all random chance, it's still a game. Hell, in that case it's maybe even moreso, because nothing we do matters at all to anyone!
So, the next time someone gripes about life being meaningless be sure and laugh, if only to yourself. Of course it's meaningless, that's kind of the point. That's what makes it really pretty incredible to get up every morning. You can do what you want, read what you like, sing however loud you want to, and fuck whatever you please. Just, please. Leave me alone to sit over here and be a huge, flaming hypocrite. And keep your damn fins off my mealworms!