why don't shelters let dogs have toys in the cages?

[?shelter puppies rule?]

I understand not putting toys in for multiple dogs but dogs that are alone in cages why don't shelters put in chew toys or even rawhide or any toy in the cage(even cats don't get any cat toys). I'd donate toys but they don't allow it. Why? it's such a lonely sad life for them at least they should be allowed a toy..
this is my local kill human society..(actually though, a dog trainer said it was the worst shelter she has seen in this state)
it really was terrible..when you walk past the cat cages, the slam their bodies up against the cage rubbing, just dying for human connection..
and in the dog section, the barking is so loud you literally can not hear your own shouting, even when you go into the small dog section through the closed door you can't hear your voice unless you shout