Exactly, my main thought when companies are being bullied for their lawful behaviour is if parliament wanted to stop corporations using a specific tax loophole,

Exactly, my main thought when companies are being bullied for their lawful behaviour is if parliament wanted to stop corporations using a specific tax loophole, it could pass a law against it. Why hasn't it? Not that it's always easy to divine its intent. This is not to mention that tax law is a lot more complex and likely to result in subtle loopholes than this specific, evidently well-known one.