what is the theme of this short story?

It had been a long and miserable winter for Wolf. His hunting had not gone well for many weeks and his ribs were nearly sticking through his skin.

One night, as Wolf was out seeking something to eat, he met a house dog.

“You are looking very well, Cousin,”said Wolf. “Here I am, near starvation, and you are clearly well-fed. What is your secret?”

“Oh, there is no secret,” said Dog. “I simply have a wonderful job. I guard my master’s house and keep away any thieves. In return, he treats me very well.”

“Lucky for you! If only I had it so easy. For me, life is a constant struggle.”

“But you can have this grand life, too,” said Dog. “Just travel with me to my master’s house and help me keep the thieves away.”

“Happily,” said Wolf. “I’d love to have a belly full of food for a change.”

While they were trotting along together, Wolf spotted a mark on Dog’s neck. Curious, he asked what had caused it.

“Oh, that’s nothing much,” replied Dog. “Perhaps my collar was a little tight.”

“You wear a collar?” Wolf backed away from Dog.

“That’s nothing to worry about," said Dog. "I wear a collar so my master can hook my chain to it."

“You are chained?” cried Wolf in surprise. “You mean you are not free to go wherever you please?”

“Not exactly,” said the dog, looking embarrassed. “You see, my master thinks I’m a bit wild and so he ties me up in the daytime. But he lets me run free at night.”

Wolf backed a few more steps away from Dog.

“Wolf, it’s a good deal,” said Dog. “I get plenty of sleep during the day, and then I am free at night. I am my master's favorite and he feeds me very well.”

Wolf turned and started to walk toward the forest.

“But wait, where are you going?” cried Dog.

“Good night to you, my poor Cousin,” said Wolf. “You’re welcome to your grand life — and your chains, but this is not the life for me.”