Hi StephaneLaliberte
This house was build at the start of the great depression that was between 1929 and 1939. So, while the unemployment rate was way up, at 25% in the states in 1933, Rutherford had this house for himself and his friends. And don't forget that they already had the big buildings in NY.
Why was that bad? I understand that it was built by a builder? Who were paid?
Don't forget the principle of the New Deal at that time - by providing temporary employment that people would be paid for it helped keep millions of Americans off the streets and getting some money - even kinda like the Bible example of gleaning.
This was done both by the American Government and by private individuals, perhaps most famously by Rockefeller - as in New York's Rockefeller Center - the project was a 'job creator' for thousands - but everything helped, even very small projects and jobs.
https://dp.la/exhibitions/exhibits/show/new-deal
It does depend where you stand politically, but the principle is - if you've got the money in times of depression, it is better to spend it to pay people to do things so that the money gets circulated in the economic system.
Then some people may be able to pay income tax, which the Government can then use to gainfully employ more people (doing things like 'public services') - it's pure economics