This has been discussed before and something similar was available in Japan
For the occasions when the website is showing something as out of stock due to raw material, production issue etc. The customer can hit a button to be informed when it is back in stock. This could be through App notifications, text/email.
Also a possible opportunity to link to stories about raw ingredients and buying.
|I need it....||Not sure, just thought it was cool|
|What part of the business does it relate to?||Web|