First, you look very much through the eyes if an US citizen.
That's funny, I am not. Greetings from Belgium, Europe! I might have used some US/English formulations as that's where the majority of the Slashdot public is coming from, but my perspective is VERY international.
There is and will be middle class in other countries, e.g., France, Denmark, Germany and even China.
Welcome to the globalised economy! As soon as there are machines to automate a certain task, they will automate that task globally - except maybe in those cases where workers are still cheaper than the capital expense necessary for the machines. But even FoxCon is now robotising while they do have cheap labor...
When you talk about the next wave of automation, which will happen probably at the end of the 2030s, you talk about global job reduction by 80-90% as almost all human tasks will be replaced.
Second, if you are a home owner, you often have a family and cannot throw away $150k.
Sure, but the 'often' cases aren't necessary to get to a million adventurers to kickstart Mars. They will not see it as 'thrown away', but being part of something historic. There just need to be enough of them. Right now there are enough people who inherit a house without being married or kids. And some who will go as a couple and even children.
Third, a goal of Elon Musk is not the same as an actual flying device which can keep the price promise.
Well, a goal of Elon Musk is as close to reality as it will ever be :-) He is known for missing his deadlines, he is not known for missing his goals ;-) Fundamental to his goal is that one million people can afford to pay the ticket, that's why he is building the BFR to use as intercontinental travel. So he can afford to build hundreds or even thousands of them. Enabling optimal use of the small 2-yearly mars-earth transfer window.
Until now he has used existing tech and technology concepts which have been evaluated for decades.
Like reusable rockets which land vertically? No, he thinks outside the box and puts all his money behind it, nothing short of amazing! And yes, still a lot of questions related with living and sustaining on mars will need to be addressed, but we can learn from our experiences on the ISS and the south pole and build on that.
His achievements are impressive, but even with that rate we are not going to Mars in the next 50 years. Not to your price tag.
You might be right, in that case the choice above would be: 'it is not going to happen'. But I'm an optimist, and if it's going to happen, it will be thanks to Elon Musk (and everybody who contributes to his success). And it's going to happen during our lifetime. For me at least, this was an extra argument to buy 2 Teslas. Aside from the ecological benefits, the fiscal benefits and that they're just great cars and that they run on Linux, of course ;-)