There is a difference between a rosin bag and one of those hand drier bags. I believe rosin is made from pine sap or pine tar or something of the like, and it produces a tacky effect on the skin, enhancing grip.
Those hand drier bags are just kitty litter or the equivalent, and they absorb moisture. They help remove moisture if your hands sweat, but they don't add tackiness like a rosin bag.
Shiv
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Listening to the monotonous staccato of rain on my desk top