Link outselling Mario is a little bit of a surprise. I suppose this was in the height of Hyrule Warriors time, so people would be after the Spinner among other things, but even so...
Mario has always been a more recognizable character than Link, but with Nintendo players, Link has been a more popular character and Zelda the more popular series than Mario since the 8-bit days. At least in most of the western world, not sure about japan.