I can certainly see the value of these cameras, particularly for nocturnal wildlife, but it could also be useful in daylight. The image quality is never going to be anything like the standard digital camera. It will also record video but I haven't tried that yet.
The benefits for me are;
1. Prove the presence of wildlife in an area/specific location,
2. Provide information on the timing of movements, with a view to taking standard photos,
3. Provide details on numbers or possibly age or sex of the wildlife in an area,
4. Give some indication of what the wildlife is doing.
Early days yet, but I have a number of holes in the ground and in trees where I would like to identify the occupants.