Answer:
They can get information from you without even have to know you in person.
They can for example know when you're in holidays, when you're posting pictures from you in the caribic.
Or also know when you're at home or not, if you're capturing one of your pictures with (f.e. "Yuhuuu Hawaii!!! I'm, going to stay there until in two weeks"), and easily rob your house, since you're not at home.