[Fists] why DXpeditions use cw?

[nz7c@cox.net]

  I'm curious as to folks' thoughts..in a reply to my earlier email it was noted that many DX ops USE primarily cw - thus most of the responses are cw.
  Being new to DX and never having thought about it - I was surprised. Is it because most of the hi-profile operators "grew up" with cw or are there some logistical reasons that make the mode the most practical? I'm not trying to express any opinion - just quite curious - thanks for any input folks.
73/Tim NZ7C