Yeah we aren't supposed to promote idolatry. True. But as for it being 'fine' to make Mecca in to Vegas, its really not fine.
A lot of people manage to save over years and then go to the Hajj, there also people who even walk there! A while ago some Indian couple did it and this year it was a Bosnian man. He even walked through Syria during the heat of conflict.
I haven't done the Hajj, i did the lesser pilgrimage when i was younger but imo it didnt count because i didn't do it out of choice. I would do it again though, I remember it being really soothing and just peaceful, well, Medina was more peaceful than Mecca. I know a lot of people who have done Hajj though and no one has come back with negative experiences as far as the pilgrimage itself is concerned.
I wasn't aware that non-muslims arent allowed in to the Dome of the Rock, its not a mosque btw, but the compound itself holds a mosque (Al - Aqsa, often confused with the Dome of Rock in terms of its importance, its also the place where Ariel Sharon went with a few hundred soldiers which is what sparked the second intifada). So unless your going there with a loaded semi-automatic or a a private troop you should be okay.
Well like I said im not sure if non-muslims are allowed there. I hope they are though.