The FBI, CIA, NSA, likely all foreign intelligence groups have feelers there.
It's the same as someone not fitting in at a party. You can see something off about them, you can tell they're there for nefarious purposes.
Legitimately anonymous posting results in either people condensing information, or inserting stuff that doesn't matter.
You can tell when an agenda is being inserted.
Take this as an example.
When an agent of the FBI, ATF, NSA or any other such organization creates posts online baiting potential criminals to reveal their intentions.
www.urbandictionary.com
Here's one less than 20 minutes old.
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