Living in the Conn. Valley, I've seen lots of Broadleaf wrappers that are as black as night that are pure and have no dye at all. Uniform 'blackness' does not mean dyed.
Dyed wrappers leave your lips and fingers stained. IMHO these wrappers are found on crappy cigars, rarely on a quality cigar. Check out a Villazon made double oscuro and you will see perfectly black wrappers that are made with love, not dye. Yum!