In Leeds we have Street Angels who patrol the city centre helping anyone who is in trouble
Street Angels Leeds
In other towns and cities they have a 'booze bus" to treat anyone who needs medical attention or a safe place to wait for a lift home
Mobile booze buses could be coming to a town centre near you
I do not think a bar or club can be held responsible for drunk revellers, though of course they should exercise caution when turning away vulnerable people. In Libby's case her mates had the matter in hand, they put her in a safe taxi and no doubt told her to text when she got home. When she didn't they'll have tried to call her, got no answer, and headed home to check up on her.
What a nightmarish and life-changing night they ended up having, so young to have experienced such tragedy. They, and the taxi driver, and the boy neighbours, and Greybeard, will forever wonder what they could have done differently to change the outcome. We can't blame any of them, though. The only person to blame is the one who hurt Libby, everyone else is suffering enough.