I see a vulnerability in that - spoofing location data is not hard. I really hope this doesn't lead down the path of transport operators introducing DRM-like ro

I see a vulnerability in that - spoofing location data is not hard. I really hope this doesn't lead down the path of transport operators introducing DRM-like rootkits, but unfortunately the concept of relying on data from devices owned by the user is always going to be at odds with preventing dishonest use. I'd much rather use a smartcard which, whilst tamper-proof and not modifiable by me, is separate from my own devices and personal data.