Originally Posted by Marylou
How do you not take the bus?
I think a couple of other posters got confused as to which bus you were talking about. There are busses that shuttle between the various terminals at CDG, and the other posters are correct that it is typically much nicer (and often just as quick or quicker) to do the transfer on foot.
You are correct that for flights that don't board via jetway, you must take the bus to get to the plane--they don't just let you wander off on your own.