Unfortunately, this is fairly typical of tire wears in BMWs. The inner wear on the rears are fairly easily rectified with an alignment - just needs a bit of "toe-in" to correct it. The fronts are not as simple, however, since there isn't anything much that can be done to adjust the camber and adding tad bit of "toe-out" to correct for the tire wear will cause to car to be "darty". But who knows, you may simply have too much toe-in on the fronts and not enough on the rears.