Since room rates are generally taxed much higher than resort fees, I'm surprised that no local tax collectors have tried to outlaw resort fees. Seems to me that the practice could be viewed as a way for hotels to dodge taxes. Although, I'm not sure that's good for guests. As annoying as resort fees are, if that part of the bill gets placed back in the room rate, the overall bill would increase (in places where the tax rates differ).
I'm also surprised that franchisees haven't complained about how resort fees affect search listings. It's less of a problem if all area hotels have resort fees. But, in mixed-markets the hotels without resort fees are at a competitive disadvantage. If hotel A is $90/night with no resort fee and hotel B is $75/night plus $25 resort fee, that puts hotel A at a disdvantage. If I owned hotel A, I'd be pressing the brand to have mandatory fees shown in the initial search results on the official website.