On the other side of that, I got on a train to go from Syon Lane to Wokingham, with a change at Virginia Water. I was running late and didn't have time to get a ticket from the machine (un-manned station) so I just jumped on the train. I asked the gaurd, who wasn't checking tickets, if I could buy a ticket, but they don't sell ticket on board anymore.
When I got to V.Waters I had 5 mins between trains, went to the ticket office explained what happened and the lady happily sold me a return ticket for the entire journey.
As it turned out, no-one checked my ticket in either direction and there are no barriers at the stations, so I could have got away without paying.