When the guest login with the App via Facebook or links account with Facebook, it is expected behavior that the user will receive the email from Facebook for security reasons.
It is not like that they have shared anything on their Facebook Page or something. It is just the notification sent from Facebook that you have logged in to the App and your few personal details like Name, Email, Profile Picture are shared and saved in their account.
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This additional disclaimer will be removed upon formal review of this article. The standard Punchh Inc. KB Disclaimer still applies, and can be found at: https://support.punchh.com/hc/en-us/articles/360040100273-Punchh-Inc-Knowledge-Base-Disclaimer
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