I think this may be becoming a widespread scam.
In fact, I fully expect someone will try it on me in the near future!
In fact, I know a person this happened to just a couple weeks ago!
It is equally absurd that she or anyone present was smoking.
1) She doesn't smoke...I mean, that is just the reality. She is not a smoker, even socially.
2) She's recovering from months of unpredictable intense seizures, so currently she "gets wild" by sometimes having a diet soda...not exactly in a "party hard" circumstance or place in life...
3) ...which is why she was the person who got the Airbnb -- SO SHE COULD COULD SUPERVISE THE TEENAGERS AND MAKE SURE THEY DIDN'T DRINK OR SMOKE.
I think unscrupulous hosts have found a scam using Airbnb's rules.
It appears Airbnb will basically NEVER take the guest's word over the host's when it comes to smoking, no matter what.
Therefore accusing some guests of smoking is no-risk for the host -- and possibly financially lucrative if there is an associated fee or a charge for "extra cleaning."