Absolutely, it is essential to always run the numbers. I was once offered a sizable rebate if I accepted a non-0% car loan, but no rebate if I paid cash or had my own financing. Since their loan had no early-repayment penalty – and I demanded this in writing – I accepted their loan and paid it off upon the first statement.
My suspicion is that that sort of offer was to boost the commissions earned by the loan brokers, rather than to move cars. Or maybe both. Who knows.
If a citation is going to point to any of the Stack Exchange Q&A pages, it is extremely important to specifically cite the exact post or answer, since – not dissimilar to Wikipedia – the quality, consistency, and biases of Stack Exchange answers is paramount for evaluating the information presented, especially factual data to be fed into an infographic.
I personally am intrigued at these $800 economy, ten-hour flights, as well as a total omission of freight cargo in the underbelly. As presented, this flight has 180 passengers and runs for ten hours. This would suggest it’s not a common narrow-body, either the Boeing 737 or an Airbus A320, as even their largest available configurations can’t fit 180 people in a 2 class setup, let alone a 3 class setup. It could possibly be the Airbus A321, though.
My point is that if it’s a widebody aircraft or the A321, not hauling cargo would be some staggering malfeasance for a commercial revenue airliner. But I can’t follow-up on any of these queries, since the sources aren’t properly cited.