Because of the horrified hush that descends whenever the subject of immigration arises these groups have been allowed to flourish. They've been all over Europe for decades and for that time a blind eye has been turned on the abuse of children for fear that the racism card is going to be played.
Meanwhile countless little ones have led lives so miserable it is painful to even think about it.
I remember watching a woman in Spain once, when the little girl brought something back she took it immediately from her and when she returned empty handed she got a clip round the ear or a whack with a stick. And no one would go near her because "we don't get involved." That was the police as well.