Shame that everyone is going to jump to conclusions rather than work out why this is stored.
Shame that some people take privacy so lightly.
Who cares what application Apple is using it for? Really. How on Earth could that possibly matter. It's literally a log of all of your whereabouts that is kept on your phone and transferred to other machines in an unencrypted fashion, such that anybody who is aware of it can access it.
Even if there was a valid reason for Apple to a)have this info, and b)copy it without your consent to other machines, to leave it completely unencrypted is beyond the pale.
But hey, there a plenty of people who's attitude towards domestic warrantless wiretapping amounts to "Who cares, -I didn't do nuthin", so ambivalence on this issue is sadly, hardly surprising.