I said maybe twice as much. You're right though, probably the average is more like 50% higher---at least that's what it is in my field. But certainly there are many making 2x as much in private industry.

Bloated administrative services are definitely a main culprit. More so than exorbitant president salaries are all the additional full time persons being hired for university "services" like accreditation, diversity awareness, PR, etc.---non education-related stuff.