Answer:
Professional thieves can track your every movement and use pattern-recognition to find out where you live. This way, they would be able to raid your house when you are not there, making the entire process much easier.
Data can also be stored and sold. It been confirmed by numerous reputable sources such as CNET. There have been many different lawsuits in the last few years which were based on the fact that the defendants had sold location data from their applications to third parties