Though it seems incredibly cruel to mess with a monkey in this way.

But according to The Sun, Bieber's monkey is completely traumatized by the whole thing:

Centre boss Karl Joachim said last night Mally refused to eat and stared miserably into space when he first arrived. He explained: "He was snatched from his mother when he was around nine weeks old. That is much too early.
"He is clearly traumatised at being taken away from his family. We could not get him to eat until we gave him the cuddly toy he was clinging to when he was delivered to us. This obviously acts as a kind of surrogate parent.
"He keeps calling a lot for company — without his toy he won't eat at all."
Bieber is unlikely to face prosecution for illegally importing the monkey, a protected species.

Via: thesun.co.uk