That’s a common practice in enterprise software licensing agreements. The organisation that is being audited signed up for this. Oracle uses audits to enforce being correctly remunerated under the agreed metrics. Nothing scandalous about it. Not sure if audits only happen for on-premise deployments and SaaS usage is automatically metered.
Oracle doesn't use node locked licensing, which is convenient for operations. However, it is also convenient for "accidentally/on-purpose having more Oracle running than you paid for". So Oracle uses "lawyer locked" licenses instead: you follow the license or else you're going to be spending some uncomfortable time with Oracle's flesh-eating lawyers.
See also the law firm in Buffy the vampire slayer.
With normal vendors/suppliers you audit them. With oracle your supplier audits you?!