Well, that's a different thing. People who go into comedy clubs go there, loosen up and wait for the humor to begin. And comedians are ( hopefully ) funnier than most of us anyway.
In the JCF, some teenaged person looks through the list of new threads:
"..hrm.. "GIVE ME JJ3!", "What good moveset would you give whatshisface".... oh. A comedy thread. WOnderful. *click* ... "Why did the elephant color his toenails red? TO hide in the cherry tree!" ....................."

It's not easy to explain the concept of what is funny and what is not.