No, I don't think the derision for Bieber is straightforward envy of either his money or his easy access to sexual exploits. It is rather more complex and subtle: he epitomises the ultimate embodiment of all that is perceived as wrong with the western celebrity culture: hollow, shallow narcissistic characters, little or no discernible talent, high pecuniary rewards with little effort or work, and irresponsible, feckless conduct.
This video sums it all up hilariously:
http://www.youtube.com/watch?feature=player_embedded&v=nw6M4XF8ZJw