This is very strange. You should have the opposite wear pattern on the rear tire if the frame of fork is tweaked.
Does your front tire track straight when you are going forward? If the front tire is off camber, the bike will want to pull to one direction or the other. Ride without hands (carefully!). What does the bike do?
Go in a straight line and have someone watch from the back. Does the bike "Hound-dog?" That's when the rear tire takes a different track from the front.