I checked into this very nice hotel at the Executive Lounge. I was handed a page with all the rules of the EL. It included the following words in bold letters: 'Casual Evening Attire' after 5pm.
Taking this to heart, I dressed up in khaki slacks and a dress shirt when I went back for the evening. So imagine my surprise when I saw a woman in a body shirt and bare foot, and men in flipflops, shorts, and dirty t-shirts. A man in wet swim trunks and a t-shirt came in and sat down, totally oblivious to the possibility that someone else might not want to sit down in the exact same spot shortly after he departed. Finally the lowest common denominator was hit by a woman who came into the EL in a bikini. She was asked to leave, which really irritated her as she picked up some food items and stomped out.
So what the hell is Casual Evening Attire? I guess it has been dumbed down to flipflops or bare feet, shorts, and dirty t-shirts. Either have rules or don`t have them, and enforce them if you have them or let people just let it all hang out.