I'm sorry to hear about your experience. I've already discussed the support response from my team as it was incorrect for you situation.
Regarding the accumulation of data while you're driving, you raise a very valid and valuable point. Yes, this can happen in some situations - the varying levels of 'noise' for certain types of shock absorbers and road conditions, coupled with device placement when in a vehicle (wearing higher is better, setting on soft surface helps) can have an impact. We hope that once a customer knows the degree to which this may happen in their environment they can accommodate through device placement and/or through the manual entry designating a driving activity on their Activity log.
By way of example, I ride a bus every day to work and have no data discrepancy with the tracker in my pocket; I drive a herky-jerky Jeep on weekends so I place my tracker in the console while driving. A customer recently contacted us because of data accumulation while driving his tractor. We pointed him to the activity "driving tractor" and he was quite pleased - he wants to wear the device while walking out to the fields, but can't readily set it down while plowing the fields.
As I said, you raise a valid point from a usage standpoint. I will talk to our product team to see if environment scenarios may be better highlighted, and I will make sure we have a knowledgebase article on the topic.
We hope you enjoy your tracker and wish you many satisfying steps.