So how could a full stacked Hero take advantage of this?
The caller makes two mistakes: first by calling light and second by not raising. Hero can squeeze and 3-bet with a range wider than he would play against the short stack alone. Why? Because fold equity against the cold caller is significant, so potentially adding dead money to the pot and so massively improving the pot odds. Since pot odds are better, Hero can 3-bet with a wider range than he could play against the short stacker alone.