I don't see how using caffeine shampoo is different from drinking coffee. Chemicals can be absorbed through skin, so the caffeine in the shampoo will surely enter my bloodstream. And if the shampoo really has the same caffeine content as 60 cups of coffee, it will give me terrible side effects.
It just doesn't add up. Either caffeine shampoo has little to no caffeine or they've put other stuff in it that counter-acts with the caffeine or limits its absorption.