But it's not the wi-fi network that's vulnerable,

But it's not the wi-fi network that's vulnerable, it's the individual devices, at least with keylogging.

That's a problem. How do you explain to tired, harried people that their devices need protection and that it's not the hotel's fault.

It's a situation they really should have known about - what's their problem - but since they don't, maybe they can read about it and sign up before they go to sleep after a 10 hour flight with 2 kids?

Then they should start paying for protection from a theoretical threat, whatever it is, but not spread the word about the hotel's unsafe wi-fi network.