come home after week or two of vacation and car is gone, sorry data was deleted a few days ago ...
We can go round and round coming up with more exotic situations to justify the situation. Maybe someone takes a sabbatical and comes back three months later. Maybe someone goes to jail and comes back after 3 years to find his car stolen. It's a matter of diminishing returns and I'm not sure keeping data for two months is really justified outside of a murder inquiry.
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probably means they store it indefinitely.
Regarding diminishing returns, sure, why not indefinitely? That kind of data volume is dirt cheap to store. One instance where it proves useful to have the data justifies years worth of storage for thousands of individuals.
Regarding justification of keeping the data for months inside or outside of murder investigation, the thing is that you don't know if data you have is relevant for murder investigation, and the law enforcement could make the relevant connection months or years after the murder took place.
Apparently this feature is not actively advertised and obviously not well known, so public isn't in an uproar over privacy concerns, but law enforcement knows about this and uses the system. The potential benefit for keeping the data is evident, so we could only discuss if it's justified to infringe on privacy of thousands in order to protect a handful of individuals, and perhaps if there is some nefarious usage of that data. I don't know answers to these issues, but I sure would be happy if data collected on me eventually turned out to be instrumental in righting a wrong done to me.
That's why I'm not as much concerned about data collection itself, only about potential misuse of it. I am fully aware that I can not expect to be invisible to the Big Brother, but I can expect that there is a system to keep Big Brother in check to prevent it from abusing the data, and making sure that storage is secure. Sure you can argue that if there is data to be used, it's going to be misused, but that is not the problem of data collecting itself.