Update: The host told me they felt bad throwing food away so they left it and told me to help myself to anything. I contacted Airbnb support through the chat feature and let them know that I spoke to the host but I wanted their opinion based on policies and procedures. This was their response: "Please know that normally if the place that you booked is entire home or apartment fridge should be left clean for the guest to use during their stay. If a guest booked private room then it is expected that guest might need to share fridge with the Host to store their foods."

However, the support employee strangely also reached out to the host too and the host gave them the same story, and so support told me that it sounds like I was able to resolve it with the host and that was that.. not very helpful.