"I have 10 weapons and 12 high-level grade-3 armor, and some low-level grade-4 pills." That man in front of Minos said. "I am willing to trade the grade-3 and grade-4 items for 10 King-grade and one Saint-grade medicine."
Beasts cultivated mainly through food resources. They could not use crystals, as they could not use cultivation techniques. And since the energy in heaven and earth was not so easy to absorb, using food resources was at the base of any beast tribe.
So they would trade items of little use to them, such as weapons and armor, for this kind of resource.
However, don't make a mistake. Even though these beasts didn't see much value in artifacts, they could fully use weapons and armor.
That was not normally possible if they were in their bestial forms. Still, they could use the benefits of artifacts when in their humanoid forms.