Without this device, they have to drive up, close and personal. They have to essentially stalk their victims. There is a greater chance of getting captured on

Without this device, they have to drive up, close and personal. They have to essentially stalk their victims. There is a greater chance of getting captured on CCTV or having eye witnesses that might get their license plate. With this device there are a few problems: 1) Parents will have a false sense of security. They may let their child wander off a litter farther, possibly out of view. 2) The abductors can passively determine which kids are likely to be farther away from their parents and determine the safest path to extract their victim. In terms of being silly: This could be a former (abusive) parent that is legally blocked from seeing their kid unsupervised. This is the most common scenario and many of the amber alerts are for this. In my opinion, if parents are going to rely on something like this, it needs to use military grade encryption and military grade implementation / process and be pentested by numerous independent researchers and come with a multi-million dollar guarantee that it can not be compromised. If that is too difficult with current tech, then this device should not exist. Rather, parents will need to stay with their children until their children are able to defend themselves.