Painted Hands as Art and in Advertising

I haven't had a chance to investigate this further, but I'm definitely noticing a trend with hands being used as a canvas for art and for advertising. What could be the underlying impetus for this wave? Inspired by body art in general, tattoo art? Or, is it that in our blasé -ness for all ordinary medium, hands are presenting a fresh... face? Do hands add a more "human" touch to the product presentation? Whatever the inspiration behind this trend, I like it!

For example, this Animated Hands collection called "Animani" from the artist Mario Mariotti

And this campaign by AT&T: