The us has approximately 80 times that many armed police officers. So, if they shot ~7,000 bullets a year they would arguably be showing similar levels of restraint.

Unfortunately, it takes less training to become a police officer than a kindergarten teacher in the US so we don't see the same level of restraint. IMO we would be better served by a smaller but better trained force unfortunately the federal, state, and local governments all do law enforcement and at the local level there often seen as a way to generate revenue making them 'free'.