Being shy has nothing in common with having thousands of fans and having concerts, derp. Look at all the gamers when they have to give interviews, haha and it's just an interview. Not everyone though, obviously.
Sorry but how is that relevant? You just said that in the same conditions of him we couldnt do it which is not true since you dont know anyone here... You are just giving your own example to say everyone would do the same as you would.
im far from a bieber fan, but hes not the only one doing playback concerts, probably 70% of the artists do it, its not all about can or cant sing, if they always used their voices in concerts, they would most likely end up with no voice, due to the number of concerts they do, singing in a stage requires more voice then singing in the bathroom or something.
Also i dont really understand why so much hate, i think its more about the bieber fans then bieber himself, he is not that bad at all, has a decent voice, plays drums, plays guitar, he is just unlucky to have the fans he has (most of them 14o girls) who too fucking anoying