At £15 per hour minimum wage, once employers' NI, pension, HR etc etc are taken into account, works out at 25p per minute. It doesn't take very long for the costs of an 'exceptional' process to mount up quickly. It's much cheaper for them to just push a button and semi-robotically send another one. Or equally refund you, rather than organising a repair.
It's why I end up doing a lot of DIY too... any time you want something done out of the ordinary, the time to even price up the job is going to add up. If you want the brake pads done on your Ford Focus, they've done it a hundred times before and the computer will give them a price including parts, labour and margin. But for a repair which is 'not on the system' they don't have a clue how much to price it, and by the time they have you don't want to pay it anyway.
Theo