Bono and those darn sunglasses

I swear that in about 99% of the current photos that I see of Bono, he's wearing sunglasses. I suppose it's part of his image. He talks about those sunglasses on page 61 of Bono:

Michka Assayas: 'What about your own sunglasses, then? Do you wear them the same way a taxi driver would turn off his front light, so as to signal to God that this rock star is too full of himself and not for hire at the moment?'

Bono: 'Yeah, my insincerity...I have learnt the importance of insincerity, the importance of not being earnest at all times. You don't know what's going on behind those glasses, but God, I can assure you, does.'

My impression of Bono was that he was really arrogant (and I'm sure that he is in a way), but he seems more grounded in his relationship with God the more that I read about him.