Being the butt of a joke and being a victim are not equivalent. Hence the distinction of "punching up" versus "punching down".
Of course it's really easy to get mixed about and think you're punching up when you're really punching sideways or slightly downwards (ie at your fellow, yet different, plebs).
"Up" generally refers to the more powerful, while "down" refers to the less powerful. I don't know what scale of culture you're referring to - if you're just pointing out that power is not fungible/transferable across subcultures, I had attempted to account for that in my original comment ("sideways").
Of course it's really easy to get mixed about and think you're punching up when you're really punching sideways or slightly downwards (ie at your fellow, yet different, plebs).