It's probably about time that McDonald's either completely revamps their menu (especially the children's options) or parents simply stop using it as a source of food for their children. Our obesity epidemic speaks for itself, but the World Health Organization has stated that processed meat is a group 1 carcinogen and red meat is a group 2a carcinogen (lower number means greater strength of evidence): http://www.who.int/features/qa/cancer-red-meat/en/
It definitely should not be socially acceptable or even permissible (in my opinion) for known carcinogens to be fed to children. It is child abuse. I don't care how convenient it is for the parents. That is not an excuse. The vast majority of these children have absolutely no understanding of how this "food" is prepared or the possible negative consequences of consuming it.