When you become famous at a young age, it is almost inevitable that you will make errors in judgement and it is even more likely that the press will be waiting to take pictures of those errors. In the case of Justin Bieber, he became extremely famous and it all happened before he even reached the age of 18 years.
Bieber has managed to keep his image very clean and stay out of trouble. In every interview he is very polite and well mannered and always gracious to his fans. It’s not surprising that his publicity team would be upset that his clean image may have been tarnished in spite of them doing everything that they can to keep it clean.