The Call of the Wild question

Just looking for some feedback on this book. It says it is appropriate for ages 7 and up. This must be referring to the reading level because it is quite violent and cruel. Am I alone in this thought? I would never expect that a seven year old would appreciate what the writer was trying to accomplish. I would think they would just be crushed by the cruelty and sadness. Definitely not for a child in my opinion!