I would be very skeptical of anyone relying on Shodan data. At one point I was trying to write honeypots myself by replicating wifi cameras, but almost all the ones on the internet I found were honeypots of some sort, and the ones that weren't were already hacked and had their web pages replaced. In retrospect it would have probably been better to get a vulnerable device myself and probe it.
If I were you, I would probably ensure that the fridges you used have residential or commercial (aka non-DC) IP addresses. Maybe Shodan uses this data for their "honeypot" label, my experience was some time ago so no idea though.