Since you automatically create prop behaviors for everything that's not a creature type, someone with a packet editor could technically try to gather from items, single gold coins on the floor for example, generating as many empty prop behaviors as he wants, that all use memory.
Why are using the behavior system here anyway, if you don't have a behavior? o.o
You should specifically check for prop type, and get the prop with GetProp ... oh, that doesn't exist. Well, you should add it xD