I learned that this actually has a name: security smoke, and it's been around for more than 25 years. The smoke makes it hard to see, so it actually reduces the loss (they can't steal what they can't see). It's also quite a surprise - and I suppose most criminals would run away rather than stick around and see what else is going to be triggered. About identifying the perp - cameras would capture their image(s) before the smoke's deployed, but criminals usually hide their faces anyways, so the smoke's not a big factor in identification.
One interesting thing about the Fujian Tulou is that the building is occupied by members of the same family clan. Imagine living with 800 of your closest relatives! Oh, the drama!
About identifying the perp - cameras would capture their image(s) before the smoke's deployed, but criminals usually hide their faces anyways, so the smoke's not a big factor in identification.