Their are positives and negatives to using any technology. Location services can be extremely useful. If you are that worried about someone knowing you location you should reconsider using the internet, or a cell phone. Both these technologies can be used to track you. Basically, in the modern world, if someone wants to track you, they will find a way.

It is always good to watch how much information you are making publicly available but unless your willing to go off the grid it's not worth fretting over.

(In the case of kids though it is worth fretting over and parents should be doing more to protect their privacy online. Simple things like restricting access to certain apps/services on an iPhone can make a big difference.)