Here with me at home, every guest I give the SSID and password to can use WiFi without any e-mail address.
So I think you bought some special software to run it in your shop. Then ask the author of that software.
Dear all,
I have setup free wireless network in my shop but I need to register every user email on my database, How can I setup this technology in my shop in easy and quick way?

Chowhound
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