Unfortunately, I don't have any knowledge of studies or statistical data that can give numbers as to how often these things happen. That said, FBI Portland released a a press release here https://www.fbi.gov/contact-us/field-offices/portland/news/press-releases/oregon-fbi-tech-tuesday-building-a-digital-defense-against-qr-code-scams that gives similar advice to what I gave before. This is the main highlight of the article.

> Here’s how to protect yourself:
>
> - Do not scan a randomly found QR code.
> - Be suspicious if, after scanning a QR code, the site asks for a password or login info.
> - Do not scan QR codes received in emails unless you know they are legitimate. Call the sender to confirm.
> - Some scammers are physically pasting bogus codes over legitimate ones. If it looks as though a code has been tampered with at your local bar or restaurant, don’t use it. Same thing with legitimate ads you pick up or get in the mail.

Since QR code crime is typically done through a phishing site, it is usually lumped in with other phishing crimes. It may be helpful to search for data on phishing crimes in general.
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