The T&C's state that "an acceptable form of ID is required" to allow people to use the travellers card.
Acutally, the T&Cs don't say that. They are here: http://www.virgintrains.co.uk/traveller/terms-conditions/ The relevant section is the third sentence of section 14 which states: "You may also be asked for a second form of signed identification to verify your Traveller Membership."
So a bank or credit card meets the criteria. This is all I am able to produce and has always been accepted without question. Frankly, I'm amazed that VT have never incorporated a photo into the membership card.
As a result of this people think they use any old card with a name on it. Bank cards are just as easily changed hands as the travellers cards themselves. Anyone who pulls a bank card on me is treated with scepticism as I am not able to identify that person by a bank card. Most buckle under 2 minutes of questioning and fess up to getting the card and tickets from friends or relatives who thought they were clever.
It's sad that some VT staff treat law-abiding passengers as fraudsters who are guilty until they can prove their innocence. I already find the carding and secondary id check intrusive, especially when carried out multiple times during a single journey. If I met this sort of tertiary questioning, the individual would get short shrift from me. Fortunately, there are still a lot of decent train managers about.
but that was before I learned that complimentary Traveller tickets are one per weekend, minimum one night away, and are subject to the same availability and limitations as many Advance fares...Although if I was a regular FC traveller and could have those on the back of my regular travel, I definitely wouldn't be complaining about the "Advance like" bit!