What is a play tube because it makes me think of those structures that kids play in at McDonalds and something like that couldn’t possibly cost $150K.
Yes, it's something like that. I imagine the cost is proportional to the size and complexity of the particular setup? The company quoted $20k just to install it, which is why my acquaintance is volunteering to do it.
Burning 400 calories an hour for 12 hours would be about 5000 calories.
Anecdotally, I know a retired guy who's been constructing a gymnasium sized $150K play tube structure for the past month, and he's lost like 25lb.