Why do mousetraps have a toy cheese?

Answer 1

There is no reason they should, except to "please" the human user. It certainly won't help the trap catch any mice as the mice are attracted to the bait by smell not what it looks like.

The best bait to use on a monstrap is actually peanut butter, not cheese.

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I believe that the fake cheese is impregnated with the smell of cheese to attract the vermine to the trap. Being fake the cheese will not be eaten meaning the trap can work for some time without adding new/real bait.