Consulting is a flaw in free market capitalism. The key idea behind free market capitalism is that if you make poor decisions, there are negative consequences for those poor decisions, regardless of your size. Now there is a way to avoid accountability in big companies: hire consultants. If they screw up, the decision-makers at big companies can always point the finger at the highly paid and highly credentialed consultants and say 'Guys, we did our best and hired the best. Who could have seen all this coming?'. The consultants are also free from accountability because technically, they only 'provide advice'. It's a win-win for both management and consultants.
The losers are only
(a) Investors, but they are often passive investors with no power to change management power structures.
(b) Customers, but they often are captive to monopolies because of network effects, moats, etc.
(c) Employees, but they usually are captive due to asset-specificity, etc.
We should all get MBAs and enjoy the gravy train.