It's simply carelessness. Let me add something else. It would be in the interest of Croatia, the real democratic Croatia, to resolve the question of the insignia used by ethnic minorities in the right way. Then, the whole issue wouldn't be a problem. The local population, still has a hard time accepting certain symbols used by the republic Croatia.
Signs are irrelevant, the essence is important.
Nevertheless, it is psychologically difficult to take a screwdriver and take that plaque down. The list of war criminals has allegedly been reduced from 150 names to 25. There are rumors that the list will be reduced even further. As far as I know, the list hasn't been reduced to 25 names, but by supposedly 20 names. Not a single amnestied person has received an official ruling, either in person or through an official publication.