You are also right about the importation of disrespect for women, from countries that have a far worse record even than hours.
"However, on the whole it still just says to me that the world contains men who will take advantage if they can, so minimise their opportunity."
People aren't so different, it's just the culture they grow up in. So if you live in a culture where it's okay to rape and you will not be prosecuted, or if you are, you stand a good chance of being acquitted, then many people will do it. Why not? Rape is fun for rapists.
So if men from cultures where that behaviour is okay come to the UK they need to be disabused of that notion. But so do some home-grown men and women.
I accept that the UK is not as bad as some countries where in order to minimise men's opportunity to rape, women venture out only with male chaperones. That doesn't mean to say they might not be raped by those chaperones once they've put the dinner on and cleaned up.
That's what people find objectionable about posters such as this: the implication that if you don't have a chaperone, you are foolish for going out. I also find it objectionable that the poster implies that all strange men you meet when travelling home alone after a night out could be rapists.