I'm in private investigator school in Louisiana, while I'm not a lawyer I can tell you that you DO NOT have a reasonable expectation of privacy in a public place here. Audio is tricky and a federal offense if not done right, to be safe I would say use NO audio, even from a public place.

Suggestion: Call a local P.I. or Lawyer and ask about the law in the specific jurisdiction of the ski resort.

I do not know how it works in US but in Denmark there have been serveral cases where a photographer have published pictures from public places, and have had to pay the person being photographed.

Eg if you take a photo of a couple kissing or holding hands, and make it available online, you will never know if one of the persons is married.

But maybe you can transfer the responsibility to the owner of the resort. But I am not sure about that.

Best regards

Morten