From the celebrity's perspective, they are just doing a job or pursuing their passion as an artist. They want to be viewed and respected as a regular person. From the fan's perspective, the celebrity represents "the Truth". The celeb inspires them.
Now, more than ever, the fan can learn intimate details about a celeb's life. They feel that they know the celebrity - even though they don't. They feel invested in the relationship - even though there isn't one. When the celeb does something to violate this trust and admiration, the fan feels violated - even though they shouldn't.
The obsessed fan now has the means to lash out now through social media, which shields them from any repercussions. This backlash takes on a life of its own when the mainstream media picks-up on it.
No wonder celebrities are left bewildered. They didn't even realize that a relationship existed to begin with.
Documentaries like Teenage Paparazzo and $ellebrity have a done wonderful job trying to change the perspective of fans and educate them about the hardships that celebrities often go through. I believe this is hugely important. Fans can be your biggest asset in the fight against paparazzi greed. They adore you and want to help. They just need a little guidance in the best way to help. Their reaction to celebrity is a natural one, however it can be changed.