Such is the nature of evil. Out there in the vast ignorance of the world it festers and spreads. A shadow that grows in the dark. A sleepless malice as black as the oncoming wall of night. So it ever was. So will it always be. In time all foul things come forth.
“It was just at this moment that Bilbo suddenly discovered the weak point in his plan. Most likely you saw it some time ago and have been laughing at him; but I don’t suppose you would have done half as well yourselves in his place. Of course he was not in a barrel himself, nor was there anyone to pack him in, even if there had been a chance! It looked as if he would certainly lose his friends this time (nearly all of them had already disappeared through the dark trap-door), and get utterly left behind and have to stay lurking as a permanent burglar in the elf-caves for ever.”