This is a very interesting topic and a hard question. Restating, the question:

"If I am paying a premium for a room at a 5* facility, it is reasonable to expect premium access to the resources? Where is the line between what is reasonable and unreasonable?"

Let me start with this assumption: 'paying a premium' means >$750/night exclusive of food/beverage. This is at or very near the lowest rack rate for most FS/MO and certainly most if not all Amans.

- I have never had to fight for any resource at an Aman. Ever. The closest I've had to a 'resource problem' at an Aman happened just a few days ago at Amangiri, where I shyly asked a 'prominent NY couple' to move over 1 seat so that my GF and I could sit together at the Chef's table. Everybody gets treated equally. Translation: 'very well' with plenty of resources. I've never had to fight for lounge chairs, umbrellas, spa appointments, anything. I've never had to wait for a seat in a restaurant or bar. We had trouble getting service at the Amanyara beach but that is a cultural staffing problem not easily solved.

- Some non-guests are welcome, even if they chew up some resources. I regularly have to fight for seats at the Bristol Lounge in FS Boston. But the locals are quite entertaining and very fun -- quite the party. Also, the FS staff does a good job at recognizing hotels guests and making an attempt to accommodate. FS NY also.

- Some places cannot even handle 50% occupancy, let alone non-guests or events. This is BAD. FS Maui is the classic example here. I am seeing recent posts that the $100 lounge chair at the pool remains the status quo. And this is AFTER the adult pool was added. I still remember the 2-hour wait for two bar seats. That was followed the next day by finding all, and I mean ALL of the chairs around the pool to be 'reserved', forcing us to put our towel on the cement. I will never return.

- I've had recent disasters with non-guest 'events'. Rosewood Sand Hill is the latest. This place already has an issue on Thursday night, where all of silicon valley descends on the bar for Cougar Night. While a fight, it was possible to get service as a hotel guest. During my last disastrous stay, the place was hosting an 'event' that choked up the entire facility: parking, restaurant, bar, pool, everything. My subsequent, heated, discussion with the GM did not go well, so I've gone back to the FS EPA and its terrible food: "Yeah", he said, "maybe we should do something."

- I've come to dislike 5* hotels that cater to non-guests with trendy bars or restaurants or other. Raffles Singapore comes to mind. This might be a good hotel. The pool is certainly nice, but the rest of the place is choked with tourists, rendering attentive service impossible. Fullerton Bay Hotel has the same problem with the Lantern Bar on the roof. It is cool but the food and service is very bad. FS BW has this issue and the staff doesn't even bother to separate guests from non-guests. MikefromTokyo will disagree, but Park Hyatt Shinjuku has this issue also, although that hotel treats guests and non-guests equally poorly.

Added comment: Too few people at a facility presents a problem also, but that is a different topic. Aman SP comes to mind here. Being the only person in a bar/restaurant is creepy.