Bah - your shoes, not your photo.
I don't know it wasn't a mistake - and neither do you.
I do believe it was a mistake as to whether the boot was to be rendered as a U-cap or a wingtip.
My belief is based on:
a) Both versions were apparently discussed with the customer - which provides the basis for a mixup, as opposed to a random different style being pulled out of the air by some unnamed person at Vass deciding to impose his personal aesthetic preference over the specs of the customer's clearly defined order.
b) They offered a discount for the customer to accept the boots as delivered, or else the option to remake according to spec.
Offering a discount is pretty universal language for "we goofed, but we're trying to make it right". And offering to remake it in a U-cap is not terribly consistent with your interpretation that they refused to make the boot as a U-cap because they felt it wouldn't look good that way.
What happens on the remake, then, if your interpretation is correct? They once again accept an order they have absolutely no intention of delivering on, then again "pretend" to make a mistake and craft the boot as they see fit? What is offered to the customer then - a deeper discount for a double "mistake". Heck, if he re-orders enough times, I guess he'll get them for free.
Anything is possible, I suppose. But that doesn't add up for me. At all.