They're certainly not the only Accor hotel in NYC to charge this. And, when I was choosing my hotel last fall, the non-Accor options all had a similar resort fee of some sort. That would be a nice Diamond benefit, to waive such fees. Here's what they charged up the street at the Plaza...
USD$50 per day, plus tax! We paid USD$163 in ripoff resort fees for a weekend.
They try to make it sound like you get value for the fee. Included with their $50 fee is a $50 daily credit for food, another $50 for laundry service and another $50 for spa services. On the surface, it might sound like a good deal. However, you'll also see above, a charge for $73 for breakfast. That was after applying the $50 credit to that breakfast. So, with such an overpriced breakfast, you're not really getting a deal. And, it would be the same with spa services, since no treatment there could be had for anywhere close to the value of the credit. And the daily credits are not cumulative over the stay, as they have to be used against charges each day. Basically a rip-off no matter how you slice it.