Why is a reward for information not offered in the majority of child murder cases. Simple it would not be effective, since the majority are carried out by family memebers or someone known to the victim. Even when they are carried out by an unknown person, it is the disgust and guilt felt by someone that knows about it and not money that is likely to bring them forwrd. The reason that the parents go on tv is two fold. Firstly it keeps the press intrest and heightens the chance of information coming in, secondly it can help catch the killer out if it is a family member. In the sarah payne case it was the mothers drive to keep the media intrest going that kept it on the front pages and at the top of the headlines, otherwise as the weeks went on it would have slipped down the news rankings. A murder, especially a child murder can be the most expensive investigation a police force can mount, so if it was purely economics big rewards would be offered, but theyre not, as they are not effective.
In the case of the robbery, however well planned, there are a number of people involved, someone will get wind of it or be ****ed off by the way they have been treated by them. The reward put up is likely to loosen their tongues and make it a very cost effective way of solving the case.
