This is a pretty common issue, I have to remind my spouse to just finish stuff. Eat it, and if it was so good.. buy more at the grocery next time.

One could try to reframe it that having it sit in the fridge going bad is a waste of fridge space/electricity/food/mental energy and unnecessary personal suffering.

Exactly the key of mindset that drives me to play through entire RPGs without ever popping a single item. It is essential that I collect 99 potions, and never consume even 1.