Well if they can't place a bill board in a metropolitan area, then I guess all schools should take them down. In the IC area there are billboards and ads placed all over for schools. CR area as well. What does it hurt to place a billboard in a larger city? I just do not get the argument here, its common business practice. Smaller school districts need something, otherwise they will just shrink and end up consolidating.
MNW is a great school and I have had the privilege of competing against them growing up. There were several students who I knew open-enrolled from FD district and it was the parents choice. Their parents were unhappy with something in the district and chose to open-enroll their child.
Where I currently live open enrollment is happening every day. There are kids changing schools almost daily because of different issues (class sizes, schedules, etc). Its the choice of the parents, where they want to send their children to school. Some parents have sacrificed a lot to send their kids to Private schools, other parents have changed their work schedule to transport their child 45min away to go to a public school that offers tennis as a sport. Its a free country and if a school is advertising, I say let them advertise.
Im also not very bright, but if it was illegal I am sure the IAHSAA/IGHSAU would be all over it. Since you haven't heard anything, I am assuming they really don't care about it and its a non-issue.