It is deliberate.
I read it in some Rolling Stone album preview. Why it was changed was not explored though.
(
Jamie_W If your life had a face I would punch it.,
Sun 6 May 2007, 16:51,
archived)
from the band's website
Though some residents of northern England might almost recognize the title, the Stripes stress they are spelling it wrong intentionally just for "kicks" and "metaphors", and to avoid a possible lawsuit from the estate of Billy Eckstine
(
HappyToast Groat froth,
Sun 6 May 2007, 17:24,
archived)