A work colleague of mine was travelling to London via Stoke, first class.

At Stoke a well-known lanky Premier league footballer got on, along with his celebrity wife and their kid. When the guard came round to ask for their tickets, the notoriously ungainly front man revealed he had left his wallet at home. He asked the guard if they could "sort it out in London". The guard agreed, leaving the couple to their first class seats and complimentary meal. On the journey the pair were organising various aspects of their showbiz lives on their mobiles (which they clearly hadn't forgotten) and arranging with their people transport to pick them up at the other end. The last my colleague saw of them they were leaving the platform at Euston where there was no ticket inspection.

Of course the stork-like goal plunker and his wife may have paid for their travel somewhere else or somehow arranged it through one of their sponsors or agents.
Or maybe the matter of payment had already left their heads as they departed Euston concentrating on the next laid-on luxury.

Seems like this train company has a policy with certain very well-paid celebrities, in the national interest, that they can travel first class, ticketless, whenever they want and settle up at their own convenience (if ever?).

So to recap
1. Choose a route with no ticket barriers or station inspections
2. Don't buy a ticket for your journey
3. Always travel first class
4. Never bring cash, cards or a wallet