Also this could go beyond the extent of "it was just a dog and it shouldn't be bugging something bigger than it"
Because he had no remorse in the slightest when ending something's life for making a noise.
Now imagine him in a workplace, with a boss smaller than him giving him stuff every day. If he can't handle a loving bark then he's pretty pathetic and wouldn't be able to handle stressful, meaningful, human yelling.