That's cops being lazy because they now don't need to write a report for your car insurance to replace the non-broken window. However, your homeowners or renters insurance may cover the stolen items. In general, there's probably nothing to do about stolen items from a car because literally anyone could have done it and it's not like your car was a sterile environment to begin with (millions of fingerprints and pieces of random DNA everywhere). To give them the benefit of the doubt, why should they expel manpower and resources over items that your insurance will replace when those resources could be put to use in investigating violent crimes? Although in reality, even with photographic evidence and location tracking of the stolen items, the cops still probably won't do anything other than write a report unless it's a very slow day.