I find these assumptions surprising:
"they seem to get what they want anytime they want"
"No guy in their right mind would turn girls this hot down."
Do you really believe these 2 statements to be true, really?
"
What would make a girl so hot intimidated or insecure?"
People are either secure in who they are, or they aren't. How hot they are to other people bears little relevence. It's how much they like/respect themselves that gives someone security.
Any truly beautiful woman knows her value can't come from her looks because one fire, car wreck, serious illness, or ? and it is gone. Beauty does not hold a particularly high value to beautiful people (say
that fast three times

)
Beauty does not equal peace of mind, joy, self-respect, or a successful life/loving relationships. No woman lays on her death bed thinking - "I was lazy and selfish, but my life was a success because, damn, I looked good."
Also, "hot" women know if you are born attractive, what credit do you get for it? - it's not like you accomplished anything - it's just a card you were dealt. It falls into the "whatever" category.
Hence their attraction to men who are not their "physical equals" as it has been expressed on this forum more than once (the bafflement of how the "ugly guy" gets the "hot babe") Often less attractive men also understand the over-valuing of physical beauty and demand substance from the women they are with. THAT is refreshing to to a woman who understands that defining self by your physical appearance is a flawed basis for an inner life.