If a company makes a profit, it pays tax on that profit. Clever accountants will mitigate tax liability, which is why airlines don't (apparently) make much profit, (when it suits them).
Good on the Virgin aircrews for considering this action. As has been debated on several other Pprune threads, Ts & Cs will never improve if we continue to accept things as they are. We need to take a stand.
Why should aircrews supplement the passenger's ticket prices or the CEOs pay packets by working poor Ts & Cs ?
A properly respected and motivated aircrew will improve company performance and profits far more than a disillusioned, exhausted aircrew, who have low quality of working life, and low quality home life.