Pretty much all human societies have some form of food on a stick. I'm not sure why, then, it's such a surprise that monkeys also have food on a stick.
Researchers are still unwilling to accept that monkeys are actually capable of the thought process of saying "hmmm, I'm hungry, I bet bushbaby would be good" and then "now, how do I get them out of the tree? I know - a stick - bush baby on a stick - my favorite!"
I don't know if researchers are startled by the seeming violence of the act. Or, if they just can't fathom that the "clowns" of the animal world are capable of hunting down food. Lions and tigers and bears do it, why not monkeys too?
Maybe it's the intentional use of tools. We've been through this before --- MONKEYS USE TOOLS, get over it. We also like to groom ourselves and look pretty. We also were in space before y'all.
Just wait until some researcher discovers that when you humans aren't looking, we wear pants. Not underpants - because two layers is just a waste of material - but pants.