Does rogaine work all over the scalp? Need advice from veterans

[Bronson]

I saw in the instruction booklet that it only works on the vertex (back of your scalp) but I've heard rogaine can work in other areas too. I just wonder though, if that's the case wouldn't Rogaine advertise this? Doesn't seem like something they'd want to keep secret. So should I apply it all over the scalp? I don't want to cause damage where I shouldn't, please help. Thanks