It looks to me like Virgin isn't actually telling the truth here...here's 2 snippets from the NZ Fair Trading Act:
From the NZ Fair Trading Act:
Bait advertising
(1)
No person shall, in trade, advertise for supply at a specified price goods or services which that person—
(a)
does not intend to offer for supply; or
(b)
does not have reasonable grounds for believing can be supplied by that person—
at that price for a period that is, and in quantities that are, reasonable having regard to the nature of the market in which the person carries on business and the nature of the advertisement.
(2)
Any person who has advertised goods or services for supply at a specified price shall offer such goods or services for supply at that price for a period that is, and in quantities that are, reasonable having regard to the nature of the market in which the person carries on business and the nature of the advertisement.
(3)
In a prosecution of any person in relation to a failure to offer goods or services to a person (in this subsection referred to as the customer) in accordance with subsection (2), it is a defence if the person proves that—
(a)
he offered to supply, or to procure another person to supply, goods or services of the kind advertised to the customer within a reasonable time, in a reasonable quantity, and at the advertised price and where the offer was accepted by the customer, the person has so supplied or procured another person to supply the goods or services; or
(b)
he offered to supply immediately, or to procure another person to supply within a reasonable time, equivalent goods or services to the customer in a reasonable quantity and at the price at which the first-mentioned goods or services were advertised, and, where the offer was accepted by the customer, the person has so supplied, or procured another person to supply, such equivalent goods or services.
***
21 Demanding or accepting payment without intending to supply as ordered
No person shall demand or accept payment or other consideration for goods or services, if at the time of the demand or acceptance that person—
(a)
does not intend to supply the goods or services; or
(b)
intends to supply goods or services materially different from the goods or services in respect of which the payment or other consideration is demanded or accepted; or
(c)
does not have reasonable grounds to believe that that person will be able to supply the goods or services within any specified period; or if no period is specified, within a reasonable time.
Compare: Trade Practices Act 1974 s 58 (Aust)