Ok. Personal headcanon.
Every 10 years, there is a party. There, mortal sorcerers from around creation assemble for what is basically a potluck. Using a mixture of spells, demon summoning and sorcerous workings, they seek to outdo each other in creating the most weirdest and wonderful wines.
The value of the food alone, easily reaches resource 5, and can easily feed entire nations or supply entire legions. The grand achievement is for someone to be able to recreate celestial wine. No one has succeeded yet.