Not so much a scam but a way to hopefully avoid being pickpocketed.
Am currently in Europe and have been a victim of theft before. I saw this wallet with the chain at Walmart when last in the US. I bought two. With the chain wrapped around my belt and secured I've been able to stop at least two pickpockets who were foiled and was able to alert others on the metro. I think I paid about USD 11. A good deal. Lots of room for cards and cash.
Similar products available on eBay and Amazon.
I can't believe people who walk around with phones, wallets and whatever clearly visible in their back pockets.
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