HMRC understand that the train ticket remains the property of the rail industry.
Maybe but EU stuff can over-rule HMRC...
I work on many EU funded projects and to get expenses paid you must produce the original receipt / ticket in the form it was originally produced in.
This means that if you buy a train ticket you have to produce the ticket to claim it. If it is printed on a thermal printer roll (as tickets are here in NI) then that's fine. If it's printed onto standard UK ticket stock you must produce both the outward and return ticket showing the trip, the date and the amount paid. If you took a photocopy of the ticket or took a colour photo of it that just wouldn't be acceptable.
(Interestingly if you buy a "print at home" style ticket then as the printout coming from your printer was the original you can just print out another for your expenses claim!)
The EU auditors do not care that the ticket is not your property - that is the rules that they follow and there's no variation. If an audit shows the tickets are missing and you've just produced the receipts then there's a problem.
If you want to get this changed then you'll need to get EU law, procurement and audit processes changed. Now that's really drifting off topic and into the realm of contentious politics!
In the meantime;
To those in my position:
Don't forget to keep your tickets.
To gate-line staff:
Sorry. I'm going to keep saying "Do you mind if I keep this ticket for expenses, please?"
Cheers,
Mr Toad