What happened to make Grey Beaver so happy with White Fang that he ordered meat to him to be brought to him?

From the text:

Of his own choice, he came in to sit by man’s fire and to be ruled by him. White Fang trembled, waiting for the punishment to fall upon him. There was a movement of the hand above him. He cringed involuntarily under the expected blow. It did not fall. He stole a glance upward. Grey Beaver was breaking the lump of tallow in half! Grey Beaver was offering him one piece of the tallow! Very gently and somewhat suspiciously, he first smelled the tallow and then proceeded to eat it. Grey Beaver ordered meat to be brought to him, and guarded him from the other dogs while he ate.