$40k a month for a year is nearly half a million dollars.
Even the actual money they spent for the month, $13k, comes out to more than $150k a year. And that's after taxes.
Obviously no one is going on Hawaii vacations every month. But this is a dumb article trying to promote the author's book.
They also had 2 small kids, so lots of more expensive resort activities could not be done.
No wonder they left $33k out of $40k unspent, this is as non-representative as it gets.