An Advance single from Edinburgh to London still costs more than a Doncaster to York Off Peak Day Return.
Short distance passengers are welcome, it just involves choosing your train at least 5 minutes before (which most people do anyway)
Right - and what if I need to travel at some point in the afternoon on a Friday but don't know when (this does happen, it's not hypothetical) and all the trains are as full as the booking system will allow (and they will be, going north at least)?
This reduced capacity will lose them a fair proportion of the Doncaster-York market (they will drive instead).
If f they are already selling a maximum of long-distance advance tickets they can't sell any more, so they've turned away the short-distance standing customers for no benefit.
If the train isn't quite booked up, how many more people do you reckon would decide that 'yes, I will book a train because I know it won't be crowded'? Is the income from those few extra advance tickets going to be more than all the revenue they've lost? Remember that the trains may actually not be at capacity on some days, but if short-distance passengers know that they might not be able to travel, they may well decide not to risk it and drive instead.
Can you not see how tenuous your arguments are getting?
It always seems faintly absurd at Leeds to see the LNER Harrogate extensions displayed with “You MUST have a seat reservation to use this service“ - it’s not as if there’s much recourse if somebody was found onboard without.
And it's not as if they will be busy, either!
Same with the Aire Valley - the evening one only has a handful of passengers even in normal circumstances.