Me: I noticed you keep leaving the grape juice and cranberry juice out.  You should probably put it away.
Housemate’s Guest: There isn’t enough room in the fridge, so I leave them out because they’re tart and won’t go bad.
Me: I don’t think it works that way.  Some juices are slower to spoil but all will.
Housemate’s Guest: Maybe, but the worst case scenario is we wind up with wine.

I’m glad I don’t drink.