The leading fast food restaurants have spent millions beefing up their security, adding burglar alarms, drop safes, video cameras and panic buttons, all of which proves useless against the most determined robbers of all disgruntled ex-employees. In 2000, a Burger King on the grounds of Offut Air Force Base in Nebraska was robbed by two men wearing purple BK shirts and ski masks who got away with more than $7,000. Joseph Kinney, the president of the National Safe Workplace Institute, claimed that wage increases, not security cameras, were the key to cutting crime. No other American industry, he said, is robbed so frequently by its own employees.