For fishermen, even if the Air Force isn't a feasible means for catching fish, there are so many other ways, like foraging for wild vegetables, drinking soup, or going to the market.
This is particularly true for someone like Lin Yu, a cultivator. He had a surefire tactic that he hadn't used yet: changing his bait to a Spirit Awakening Elixir.
Because this tactic took very little skill and his apprentice was standing nearby, Lin Yu held back and didn't make the swap.
When Lu Bei returned to the entrance of the mountain with his catch, Ding Lei opened his window to look outside and quickly ran by his side, chirping and questioning about the reason for his night out.
Lin Yu took note of this scene and nodded in approval. They had a good relationship, and the little fox seemed to trust Lu Bei. He'd overthought the idea of raising a demonic pet for amusement.