If it was just the 7 year old, a 1/2 mile is probably a bit too far, but with her 11 year old older sister? Please, this is absolute craziness..
Yes they could get snatched, but so can your 15 year old daughter or son.
I would throw this out if I were the judge, or better yet if I was the DA just refuse to put it before the grand jury. Unless there is something else going on here not reported, this is not a crime.
When I was 6 we lived on a farm and had the Monday to Saturday newspaper delivered to our door. (The morning bus driver would throw it out when he went past, then the dog would find it and bring it the rest of the way).
When I was 6½, they introduced a Sunday edition, parents did not want to order it sight unseen, so that first Sunday, I walked one mile to the township by myself to buy a copy.