Here's why:

* They eat a variety of foods: While their diet is primarily fruit-based, they also consume leaves, stems, insects, and even small mammals like monkeys.

* They have the teeth and digestive systems for both plant and animal matter: Their teeth are designed for both chewing fruit and tearing meat. Their digestive systems are also capable of processing both plant and animal matter.

So, while they are primarily fruit-eaters, they aren't strictly herbivores.