Wow, did not realize this was a rather common thing? Here (upstate NY) it's not unusual to have them hit by snowplows, but then the town replaces them - eventually.
I do think kids need more supervision. Last night, we were coming home a little after 9PM. Not quite dark, but getting close. Several kids (10-12 yrs old, I'd guess) were riding their bikes in the school bus loop. Yes it's lit and yes, it's not the road, but still - shouldn't kids be in by then? They might have been safe where they were, but still had to ride home. I don't think I was allowed to be out of the house past 9PM until I was 18!