I think for the sake of balance... if you used a weapon that was not as properly designed (like a butter or kitchen knife compared to a hunting knife) it would have a chance to get stuck in a zombie. OR if the durability of the weapon is low, it'd have a chance to get stuck in the zombie. Otherwise you just ramped up the difficulty x100 or x1,000% since you take away reliable weapons. Imagine you spent forever finding your first axe, "YAY I HAVE A GOOD WEAPON" you think, but the first time you swing it at a zombie when a hoard is approaching the random chance proc's and it gets stuck in the zombie. Good luck getting or finding that zombie ever again while your running for safety to retrieve that axe! All in all, it could be cool. I just think it'd have to be related to either improvised weapons or low durability.