Praise be to Allah.
Taking photos of pilgrims in the place of worship is not permissible for two reasons:
Firstly: they are doing that so that they can keep the pictures for memories, and any photo that is intended to be kept for memories is haraam.
Secondly: that is usually not free from showing off, because people take pictures to show to others that they have done Hajj. Hence, as the questioner mentioned, they raise their hands in supplication when they are not actually offering supplication; rather it is only for the purpose of taking the picture.
But if there is a need for that, because this man is doing Hajj on behalf of someone else, so he says: Take a picture so that I can prove that I have done Hajj, then after it reaches the one who delegated him to do Hajj on his behalf he tears up the picture, then there is nothing wrong with that, because there is a need for it, and the purpose behind it is not to keep it for memories. End quote.