That baby name graph is showing how popular names are over time. The NYT Box Office graphic does the same - http://www.nytimes.com/interactive/2008/02/23/movies/2008022... .

This kind of graphic is bad for showing exact numbers, good for showing relative share during time and change over time.

But the graph in the parent article wasn't making that comparison, so yes, it was a stupid, pet peevey way to do a graph.