This is not terribly surprising. I have many clients that are either currently using Air BB as an income strategy or are looking to get into it. While many communities are far more open to it (ski country seems to have accepted it better) Denver is still leery.
In addition to city regulations mentioned in this article, HOA's have taken it upon themselves to restrict all rentals to 3 month minimum leases in order to eliminate short term rentals. Going forward, detached structures, or smaller communities with either no or self managed HOA's may be the way to go for buyers looking to invest in the short term rental market.