Hi, My name is XXXXX XXXXX X am your Etiquette Expert.

Thanks very much for your question. The correct etiquette is that the person that hosts the party and presumably arranged (paid for) the food and drinks would be assumed to want any remaining food and beverage items after the event. Further it is normal when the event is being held like the one you describe for the host to proactively tell the tenants to help themselves to some (or all) of the remaining items. It is also normal for guests who bring items not to take them when they leave if they are unopened.

In this case it does not seem that the host proactively communicated their intent vista via the remaining items and you have taken some items. For the remaining items I would store them somewhere as the onus is on the host to come and get them. If other tenants take them so be it.

Good luck with this!