A grocery store is where I first encountered bar codes. Now bar codes seem to be everywhere. This use is probably not new for many people, but it’s my first time to see bar codes on a for-sale sign in front of a house. In this instance, a bar code has replaced an information flyer. You have to have a “smart”" phone to read the bar code.
It may take awhile to judge whether the bar code is as effective as a flyer. Not everyone has a “smart” phone.