Pop music is not one cohesive entity, there's a large difference between something like Taylor Swift and The Black Eyed Peas.
They are all popular for a reason. Some things are just made to mindlessly dance to like "Like a G6" or the Peas. And that is fine, if people want something mindless to dance to they should be able to have that.
Then there's the sweet hearty things like Bieber or Taylor Swift which as much as they are hated is fine too. Tween girls want this kind of love-centered sweet singing and they should be able to have that aswell. Both Bieber and Swift have actual undeniable musical talent, and according to the industry atleast Taylor writes her own songs.
Then there's the big person-driven popstar. They can be manufactured and without very much musical talent,(proffesional songwriters, dress pickers etc.) See Britney Spears. Others may have actual musical talent and write their own stuff like Gaga (there are most oftenly a producer in charge of the backing track though, much like how it is with rap). These thing are always catchy and well produced, to make them easily likeable. But really, there's nothing wrong with that. I mean, how can it be wrong to make music people will like?
Marketing obviously plays in, but not even tweens will buy an album unless there's atleast one song they genuinely like. And then again, some people doesn't have to be marketed. They are already innately "cool". Hating pop is pointless, it's not one cohesive thing. Liking or disliking individual bands or artists (like i do) is far more reasonable. But even if you don't like them, talking shit about them will only serve to A. Anger people who like them B. Have someone agree with you, at which point you're preaching to the choir C. Alert other of their existence. They win in all the above cases, and acting like an ass towards someone because of the music they listen makes you an douchebag. It doesn't matter if it is hipster rock, metal or pop.