I think the legality of operating an AirBNB out of a residence that you own depends on the zoning ordinances that the property is in. (Renting out your farmhouse is probably ok; renting out your suburban or urban house or condo as a business proposition probably violates zoning ordinances and would require requesting a variance from your local governing council with appropriate public hearings and notifications to your neighbors.)
You are correct, but I disagree with those zoning rules in general. Specific zoning rules that prevent behavior that is significantly negative to the neighbors I'll allow, but most zoning is about keeping some other class (generally blacks or poor) out.
