The difference is that the over zealous CO in that case was searching dwellings. There is a distinction in the Open Fields Doctrine. CO or game wardens, what ever you wish to call them can at will search "open fields" meaning pretty much open land of any kind whether it be fields, woods, waters etc... They cannot search buildings or their curtilage without first obtaining a search warrant and that requires probably cause that a crime has or is being committed. See:
