toptoottom.
Birddog states it best in his last paragraph which I could not have said better:
The US has a pretty mature approach to Self Regulation, that works pretty effectively across various types of legislation... Every so know and then people/organizations need to be reminded of their self regulation obligations yes, it does not mean the right to self regulate, when it works for 99.9% of the time is at fault.
As an observer with a "safety pilot" who was familiar with the area, you obviously have your opinion about the Vegas airspace. ATC is under no obligation to give you traffic information---the radio would never be quiet. Amazingly---one can drive safely on a freeway with thousands of cars and NO traffic information---why? Because everyone follows a set procedure or pattern. As for your Hawaii experience---I am guessing you were not on Kauai.
As for the night over densely populated area---I flew the San Francisco area for 8 years--at night, single engine----the rules in the US are completely different to what you are used to---that does not mean it cannot be accomplished safely.