Because TOCs▸ get all the revenue from an Advance Purchase fare when the journey is wholly on their train(s). If the fare is a walk-up one there's a very real chance they'll have to share the revenue with other operators. So, if anyone is fool (fooled by the system, not stupid) enough to buy one of these APs that are more expensive than the corresponding walk-up fare, that TOC is quids in.
They are all private enterprises, tasked with minimising costs and maximising revenue - so they will each seek to offer tickets at the highest price they can, based on the availability of seats 'on the day' versus 'advance booking' discounts.
That for me explains the advance fare that's 30p cheaper than the off-peak single then. I suppose in
XC▸ 's eyes it's worth a shot to get the whole ^5.60 rather than perhaps having to share ^5.90 with
FGW▸ (I'm guessing)... and I do know people that would get that ticket because it's slightly cheaper, and I guess if you did get that ticket every day (perhaps?), over a year I guess that is a decent some of money you would be saving.
Thanks bignosemac and CfN, you learn something new every day as they say!
I'd be less charitable in calling it 'market forces' though. I see it as gaming the system to gain advantage. But then should I really be overly concerned when I, as a customer, also game that system (within the rules) to my advantage?
I'm not sure I am overly concerned with 'gaming the system' like you say providing it's in the rules. And if I'm not breaking any rules, than arguably I'm not doing anything wrong? Plus, if the TOC's can do it to us, then by virtue we're quite allowed / entitled to do it back? Or does that mean I am stooping to their level by doing so?
E.g. whenever I get the train anywhere mid to long distance, the first thing I do is look to split my journey. I know off by heart that I can save ~^9 on a walk up super off-peak day return from
BRI» to
PAD» simply by splitting at
DID» (ensuring my train calls there, of course).
It did surprise me when I gave this advice to some friends, and they were more concerned with the amount of tickets they then had, as opposed to the money I'd saved them!