They are what they are.
The casinos charge them, it's up to you if you want to pay them. Most casinos waive resort fees for their top tier players.
Ask yourself this- If The Ventetian had sent you an offer for $40 a night, no resort fees would you accept it? There is no right answer, it's a personal choice. I have a friend who drove from Vegas to Laughlin for a three day weekend. Upon check in he as told there was a $10 a night resort fee. He blew up, and refused to pay it. Got in his car and was leaving town when he realized he was blowing his long weekend over $30, and sheepishly returned.