It's not a terrible thing to add a bit of cream or sugar to coffee or tea.  Sometimes some additions (lemon, ginger, cream, cinnamon, sugar, etc.) will bring out a different flavor in the coffee or tea, so it's a new, different way to experience it.  But the abominations at Starbucks are just out of control.  It's not about experiencing the taste of the coffee, it's about covering it up COMPLETELY with sugar slop.  They're drinks only fit for hummingbirds, really.