List of legitimate reasons for a refrigerator, an oven, a stove, a washing or drying machine, a microwave, a coffee maker, a sink, a garbage disposal, a toilet, a shower or bathtub, or any other home appliance to be connected to the internet:
- Get notified if a compressor fails, refrigerant leaks, or a door gets left open
- Catch failing fans, compressors, or defrost heaters before they break
- Automatically log temperatures for food safety inspections
- Optimize defrost cycles and compressor operation to save electricity
- Let technicians diagnose problems remotely instead of driving to the store
- Reduce power usage during peak electricity rates
- Monitor fridges and freezers across multiple stores from one place
- Track energy usage and equipment performance over time
- Get alerts when power goes out or equipment doesn't restart properly
This is the only one that requires remote write access, and only when "peak electricity rates" means a dynamic pricing system. But it doesn't actually need full Internet access. Instead, prices can be streamed via data diode to a local processor which calculates correct temperatures based on this information. This calculation should set reasonable limits on allowed temperature, so even if somebody sends false pricing information it's just going to waste some electricity and not destroy all the food.
>Optimize defrost cycles and compressor operation to save electricity
Assuming this means something different from "Reduce power usage during peak electricity rates", I don't see how it needs Internet access at all.
All the other points are monitoring tasks that can be done with read-only access via a separate data diode.
Even the remote diagnostics is of questionable value at best. You can do remote diagnostics just as well with a faxed printout of system information and having store staff do manual resets at needed. Remote diagnostics isn't going to solve anything that requires more than a reboot, like replacing a compressor coil, anyway, so you're going to need service staff driving to stores for these with or without the remote diagnostics.