Auditing in general is profitable, but it's mostly due to it being automated for people that aren't making 7 figures. Auditing the not absurdly wealthy is also generally a positive revenue. Auditing the extremely wealthy tends to not be a great net benefit as the costs of lawyers and court time outweighs the settlement check at the end. There's an argument to be made it's worth the cost to ensure the ultra wealthy do actually pay though.