Jewelry Windows Do Jewelry Store Owners In NYC Have To Empty Their Shops Every Night?

Do jewelry store owners in NYC have to empty their shops every night? - jewelry windows

Yesterday we were in the Diamond District of New York in about 6 hours. There were two large trucks and loads of security guards, and they carried on trucks registered pkgs. While we were walking on the street, we noticed that every window of the shop was completely empty of jewels. Is this normal? Who knows what's normal for this region?