Security through Obscurity is no security at all; just ask an ostrich. (Yes, yes, I know.)

However, this doesn't mean you need to advertise anything. Would you feel the need to warn your neighbours about, oh, the chemicals under your sink? The workshop full of tools? The sacks of fertilizer out back, and the jerry can of diesel? Kitchen knives? Electrical outlets?

And as Mark-II points out, would you casually mention your catalog of jewelry, or other valuables?