Absolutely brilliant. It's this sort of stuff that might bring back the old arcade as this system is too expensive for home owners.
At an investment of $650k just for the simulator, and assuming you'd like to make that back in a year -- which is kind of a long cycle for video game content that gets stale quickly -- the operator would have to charge about $300/hr for access. This assumes they could sell 6 hours a day for 365 days, which is so overly optimistic it's laughable. At $600/hr, you might see the light at the end of the tunnel at a year, but who is going to pay that kind of rate outside of the DoD?
I suspect there are some whopping economies of scale to be had here, though. This was a one-off and prototypes do tend to be expensive.
BTW, I'll bet 2/3 the cost was that military-grade omnidirectional treadmill. Mass-produce that and you're back into the realm of possibility.
Are you kidding, at $650k, that's too expensive for arcade owners (do those still exist besides collectors?).