Despite what some politicians tell us, the federal government is a master at wasting money. Not all of that waste is due to sinister plots intended to defraud the taxpayer. Much of it can be put down to old-fashioned incompetence.
Presidents of the United States do quite well for themselves once they leave office. So well, especially in recent years, that some in Congress have tried to curb the amount of taxpayer money handed out to ex-presidents. A bill even passed in 2016 that would have applied modest curbs on ex-presidents' expenses.