I regret to say this, but some of the world's greatest legends have freestyled.
Pelé freestyled, Garrincha freestyled, Maradonna freestyled, Rivelinho freestyled, Van Basten freestyled, Cruyff freestyled, Michel Platini freestyled, Socrates freestyled
Now let's take a look at some modern players
Ronaldo (both C.Ronaldo and Luis) freestyled, Ronaldinho freestyled, zidane freestyled, figo freestyled, henry freestyled...
I think here's enough proof that some of the world's greatest do freestyle
Freestyling does help and I think it really trains the feet. This summer I am going to practice juggling the ball so much and then learn to freestyle because I am sure my game will improve dramatically.
(I found a similar post here: http://www.soccerpulse.com/forum/index. ... 38408&st=0
and here Owen4Ever really talks about why freestyling is not useless. he also includes the legends like I have, and he talks about how your feet is improved.)