Why do you assume it doesn't?
I realize it's not always that way... but is often enough.
This seems like confirmation bias. Pastebin gets I don't know, thousands of pastes a day. How many did you check versus total traffic in a given time? Stop suggesting that it's a den of thieves if, apart from legitimate usage, thieves also find it convenient. Thieves find email convenient as well. Getting rid of pastebin doesn't solve any problems.
As for the "creative cloud," it's actually more expensive than buying the software.
I know. But my point was that, for creative cloud users access to all of their Adobe software and the admin panels for their BC sites fall under a single Adobe account login. It's a real problem if it turns out Adobe puts little effort into database and password security. I mean I'm an idiot when it comes to this stuff but even I know to use PDO and blowfish.
No need to toss in a man of straw here. Anyone who's been aware of text-sharing sites since such things existed, knows that the abuse (copyrighted, illegal, ill-gotten material) far exceeds "legitimate" use. In fact, one could argue rather easily that MegaUpload had several magnitudes more legitimate use than pastebin.com (and similar).
The typical structure of an mysql dump is a rather easy thing to automatically sense. A not-complicated regex could easily sense the pasting of alternative formats. Mr. Vader could easily reduce his workload in dealing with takedowns by simply injecting a little code that preemptively enforces his terms of service.
Long text with reporter bylines, also easy to sense.
Really long text with bibliographies, also easy to sense.
I could go on. ;)