Monkeys in the vineyard: Pests or thieves?

The German-language SpiegelOnline has a little story on monkeys plundering vineyards in South Africa. The best part of the story are the pictures.
I sent the link to some friends and one, Jim Lapsley of UC Davis, responded with this email:

Many years ago my colleague Carole Meredith attended an OIV conference in South Africa and visited the vineyards. She was surprised to see vineyards protected by electric fences (and got a good picture of one) -- "to deter thieves?" she asked. "No," was the reply -- "for Baboons".
Because of cost and availability, the fence wasn't always charged. The vineyard manager described a troop of baboons coming to the fence, looking at it, and then one of the older baboons took a young one and pushed him against the fence to see if it was on! An example of tool use in non-human species!  Jim

Rolf