What is the law about Halloween candy, treats?

I have heard:"no unsealed, unwrapped". But is it a suggestion, or, law?

I've never heard of anyone arrested over this. I've heard of cops going to someone's door over it, but just once.

I would love to give them something healthier, like apples, nuts. I remember them handing out cigarettes (for my Dad!) when I was a child!

I have some toys that don't go bad if you can't give them away, and are healthier.