I have to second to this, to an extent. A clothing, though dependant on the item, can and should if bad luck, break or tear from a zombie or a strike with a melee weapon with a sharp edge. But when talking about bullet penetration, since currently you can ruin a clothing with a single rifle round, this is wrong.

Instead, a rifle ammo should go clean through with a chance. This chance depending how filled the clothing is with hard items, eg compare a jacket with 4 slots and a vest with 8: jacket has a lot more area of cloth compared to the vest, considering pocket space too. In other words, its even much more likely that a bullet wouldnt damage an item on jacket than the same item in vest.

And yes, one bullet hole in a clothing shouldnt make it ruined.

I dont understand how one single bullet can hit everything in your inventory. And how can a zombie hit destroy a can, unless they have wolverines knives.