Being a celebrity can be a very responsible place in society. Celebrity life is part'n parcel of certain professions especially in the field of acting, movie making...most fields of art. Sometimes you really deserve the breaks you get. The transition from being a struggling artist to a filthy rich artist of sorts is one you really deserve. It's worth the struggle. But not all in the business have earned their way up. Some of them have had it in their blood. Atleast one generation of their families would have had something to do with the business. As children, they have been privileged enough to get access to film sets, studios...just hanging around-sometimes playing a role. The business is not new to them.
Another factor is that all celebrities are rich (an attribute which the fans that worship them give them). Growing up with everything the way you wanted could make you cranky. Of course, the advantage there is that they can afford to be cranky- having things the way you want them. They have all the money in the world to do everything they could possibly want to. Even if they don't fit in that well they have their familys influence to bank upon.
One thing that it doesn't teach them is the worth of their fate. There are even greater artists who have really struggled and they know the value of the hype that surrounds the industry and the money that that it brings them. It is acceptable to have people whom really have no reason to live and consider life worthless because it really has nothing for them doping and being drawn into addictions. But why would one want to do it if everything is going for fine? I suppose that proves that money isn't really the key to happiness. Despite their ridiculous ways, they still remain on the top of the list. Despite their escapades, they will tell you that for everything you get you should consider yourself grateful. They are right. They are saying it because they earned their way up and if they seem to contradict their statements in that respect by their actions, they have earned the right to fully use their privileges, which they have struggled for.