Perhaps you'd care to tell us how a "space tourism industry" would benefit 99.9999% of the citizens of this planet.

Getting millionaires or billionaires to part with their money can be difficult. The 'space tourism industry' is getting them spending, rather than just building up their financial assets. Their spending (even on something so, apparently, pointless as space tourism) creates employment, and generates more spending further down the supply chain. All of this spending also generates taxes, which the government can then spend to generate more jobs and thus more taxes.
I'm sure some would argue for preventing the millionaires from spending, in which case they might just leave their millions to the next generation of millionaires, who can also just sit on the funds.

Money is the oil that greases the wheels of industry.