Okay, I'm a frequent flyer, though not to the level of Ben (though I did once go LGA-ORD-DEL-ORD-LAX-JFK without leaving the airport in Delhi to get to Executive Platinum on AA).
Typically what Ben is doing is flying fares where the cost of the fare is lower than the equivalent value in miles, or where he can game the very complex rules associated with a frequent flyer ticket to add on a free leg or free flight.
So, for example, for my honeymooon I was able to snag round-trip tickets in business class from NYC to the Maldives. Once I had those tickets, I worked the frequent flyer system to move the dates around and add on a stop in Tokyo in First class for a couple of days for about $10 in extra taxes and fees - total retail cost of the tickets was close to $30k, our total cost was <$250. In terms of frequent flyer mojo, this doesn't even count as journeyman-level skills.
On top of that you have all of the points he's getting for using various branded credit cards, maximizing bonuses, giveaway offers, etc.
The only way I'm aware of to get FF points when you are flying on an award flight is when you get hit with IRROPS (irregular operations, usually due to weather and mechanical issues), and at the airport they rebook your award ticket to be a revenue ticket at no cost. It's something the airlines have discouraged their agents to do for obvious reasons, and they've tried to make it easier to rebook award tickets, but
still if you're a top-tier elite, there's 50 people that need rebooking behind you, and you're on an award ticket, decent chance the computer will spit out a revenue ticket to replace the award ticket that is no longer valid.
Well, the point of miles is to keep you flying on that same company, why not keep giving them?
From an incentive point of view it makes sense, otherwise, spending all your miles would be an opportunity to jump to another airline.
This particular abuse seems like an extreme case, and really, what is giving a seat to one guy who goes to extreme length compared to the returns on the general customer base?
Perhaps he buys a regular fare ticket at a deep discount, on a miles-rewarding credit card, upgrades it to first class using miles, then pays the cost of the original fare using some other mechanism that requires use of the miles to be remunerative. As the article mentions, finding anything wrong with the aircraft could be converted into a $200 or $400 credit.
By invoking certain rules or offers, you can actually get many more reward miles than the actual distance of the flight. That's why a large part of the practice is spending as much time in the air as possible.
Using those near-currency credits to bribe the airline employees with the airline's own stuff is likely another key part of the "fly free" strategy. The employees have some discretion in how strictly they enforce their employers' rules. Make friends there, and you have an easy flight. Make enemies, and you will have trouble.
There has to be some mechanism that makes this works for them, otherwise they wouldn't be doing it.
This article reminds me of one I read wherein a Chinese man bought a first class ticket for gratis access to the airport lounge, ate there for free, and re-booked his ticket for another day. Months worth of meals for the cost of one fully refundable first class fare, and he never explicitly broke a single airline rule.
This is just extreme couponing. This is the airline equivalent of walking into the checkout at your local grocery store with 3 carts full of stuff, and walking out after getting change back from your nickel.
wouldn't removing this simple feature nullify what he's doing or at least a great deal of what he's able to accomplish?