I hit these areas everywhere I go and have found a bunch.
Here is a tip I have been telling people to try for a long time that extends your idea a bit further.
Grass islands in parking lots.
When people walk over these to get to their cars they pull out their keys and just like in the area you pointed out other things come out of those pockets, too.
Not only that, rings, bracelets and necklaces can fall off and nobody hears them drop.
One of my favorite sites of all times was a parking lot in a high school I hunted several times back in Alabama.
Over $30 in clad, several silver rings, tools, all kinds of odd and ends came out of here including 2 nice silver necklaces and 2 gold rings.
Here in Kansas, I hunted the same type of high school parking lot and so far a ton of clad and about 5 silver rings have come out of that one.
I had 15 minutes at another one waiting for my wife at a doctors office that was located next door to a third one and three swings got me another silver ring.
Scour every path to a parking lot that you can...but look for the sites with those grassy or chip covered islands, too.
This is a pic of that site in Alabama to show you what I mean, and just some of the things I have dug in these type of sites.