The most obvious use of the data appears to be by credit card companies to detect fraudulent use of a card and decline those transactions. This is something I'm relatively comfortable with, though it's plainly in the interests of the bank and I only indirectly benefit from the tracking.
The most obvious use is insurance companies looking for excuses to deny claims.
With the caveat, for course, that people are not always where their phone is so this taken on its own would be circumstantial evidence: one would hope decisions are not made directly based on this information.