Because fighters are martial characters. They are skilled in what they do, but what they do is mundane. They swing a sword (or axe, halberd, spear, etc) and do it with style and even what appears to be superhuman skill at high levels but they are fundamentally non-magical.
I swear by all that is holy that if 4e has fighters with actual magical powers, not flashy, cinematic, non-anime moves but actually magical crap sputtering out of their swords I will not buy another thing from WoTC. If that crap were to be made a part of the core D&D assumptions regarding what D&D warriors are like I will not DM or play 4e.

I would stick to Conan D20 and True20 and pay no further attention to D&D from that point on.
D&D warriors are Conan, Aragorn, Beowulf, King Arthur and not friggin Inuyasha. ::chokes back some vomit::
Wow, I found my deal-breaker.....lucky me. :\
Sundragon