I am always puzzled by folk who want to treat wild animals as if they are pets. Feeding monkeys is a no-no, and in fact makes them dangerous. A male Long-tailed Macaque has teeth that make a domestic cat's teeth look like toys. Ditto claws. And we all know how much damage a cat can inflict if they put their mind to it. Wild animals accustomed to being fed get mad when they are not. Macaques are predators and killers in the wild. In close proximity to a human who refuses to feed them, they are vicious.
They are also intelligent. Here is one trying to open the doot to our hotel room. The only reason he didn't succeed was because it was locked as well as closed.