Almost every Swiss male has a gun at his house, because of the militia-style organisation of the Swiss Army.
Also, the federal legislation allows the free purchase of semi-automatic firearms by Swiss citizens and foreigners with permanent residence, though permits for carrying in public are issued only restrictively. There is proper vetting before you get a gun license. Stricter gun laws were rejected in a referendum.
Quite a few guns around there as well, but not much gun crime. Culture could play a big role here.
Interesting. I will have to see if somebody has done a psychological or sociological study on this. I'm sure someone will have done.