If the OP had gone up them, ticket in hand to ask to be let through and they had said "No, put in the barrier." then you might have a point. The OP put the ticket (railway property) in the barrier when he shouldn't have. Getting a specific ticket back can be a time consuming process, during which time they aren't able to do their 'real' job.
It sounds unfortunate, but not terrible.
I still think it is terrible. Surely part of their job is to deal with passengers and their issues, so getting a ticket out of the barrier for the OP is doing their real job.
What about a similar situation that I had at Cardiff Queen Street station last year? I had a ticket to travel to Cathays (1 stop further than Queen Street) but was breaking my journey at Cardiff Queen Street to meet a friend. I put my ticket in the barrier but it kept hold of the ticket, even though it should have given it back to me. Thankfully the staff were very helpful and fished through the barrier to give me back the ticket, but had they not what should I have done? I had no idea the barrier would retain the ticket even though it still had more validity.
I think for future reference though, if you need to retain your ticket for delay repay/passenger charter claim, best make this known to barrier staff in person.
As above, what about cases where you are just making a break of journey or something similar where the barrier retains the ticket when it shouldn't? At the end of the day barrier staff should ALWAYS give the ticket back if there is a decent reason for the passenger needing it.
Slightly different circumstance... But if you'll bear with me!
Travelling on the return portion of a Radyr - Wrexham General Off Peak Return, stop short at Cathays, so I could drop off some stuff at home before heading on to Radyr, I'd been delayed an hour by ATW so needed the ticket to put in a claim.
Barrier swallowed the ticket as the staff there refuse to let you through until the ticket has gone through the barrier. (Which I can partially understand). Member of staff then refuses to retrieve the ticket from the barrier as once a ticket is swallowed it's used up apparently.
Sent off a complaint to ATW and I received a refund on my extra Cathays to Radyr single I needed to buy. Assurance that staff would be retrained at Cathays. Assurance that staff should ALWAYS retrieve a ticket that still has validity and that barrier staff across there network should ALWAYS retrieve a ticket if the passenger needs to make a claim.
Food for thought I think, though I accept it's different TOCs involved here.
Kind of similar to my experience then, except the staff were a lot more helpful for me. Weird considering how close Cathays and Queen street are! I hope ATW have fixed the obvious issues with the barriers around there!