NZ Inland Revenue gives taxpayer details to social media platforms

Did they not ask themselves the obvious? - if the hashing procedure anonymises individuals appropriately, how could that information then be used to target individuals for advertising?<p>Do they not realise that LinkedIn and other social media companies are the very organisations we want our privacy guarded against?!

Hashed or not, why would the tax authority offer individual tax payer data at all? And does it at least increase their revenue?