Art in general serves no practical purpose - as such, it fits the dictionary definition of "useless." Does that make it not worth peoples' time?
It's a distraction, but we, as a species, need distractions, or else we get burned out, jaded, tired, we go insane, we feel withdrawn, we have no outlet for creativity or pent-up emotion. Whether it's humor or beauty, it's still "useless," and yet it's still needed.
None of those sites you linked to are "crap" either, at least not to me. They're bizarre, funny, silly, and they represent at least some effort being put into a joke. If you want to find actual crap, try trolling Geocities for a while.
Hell, even goatse.cx has its purposes and its audiences. It might be unsettling to some people, but at least it makes them less (heh) uptight, right? It catches people off-guard, and it makes them pay more attention to what they click on before they click on it, in theory. (Of course, some people never learn.)
What use is something like explodingdog? It makes you think, it's an outlet for emotion, it disarms you, it reminds you of the beauty of the world if you're willing to be naïve enough.
What use are toys? I just bought myself a razor scooter. It's not exactly the most practical form of transportation or exercise, and hell, they're damned silly. But I like silly. If I don't have enough silly in my day, I go bonkers, and we wouldn't want that, would we?
I don't see how one can effectively file things which are funny into the "useless crap" category, in any case. What kind of anal-retentive, humorless freak are you to believe that?
"Is not a quine" is not a quine.
I have a master's degree in science!
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