id scanning isn't always a bad thing (Score 1)

Why is everyone so against scanning of id's. I work for a nightclub in a chain of nightclubs in manitoba canada, and we have been using id scanners for over a decade. We have never used police or government agency databases when checking id's, the only part of the id we scan is the top face of the id, all information is locked up on a server in the GM's office and is only stored for 7 days. the whole point of scanning id's is to identify trouble makers after the fact either to press charges or to bar them from re-entry for instance if an incident occurs on our property and someone gets hurt by another patron we can look the persons id up and hand it over to the police