In reply to Climbpsyched:
https://europa.eu/youreurope/citizens/consumers/shopping/guarantees-returns...
These are your customer rights in Spain (broadly governed by the whole EU rights).
Simply (as in most EU countries), during the first six months after purchase, the burden of proof is more on the seller, and the customer protection is pretty high.
You should be well protected but you should have asked the shop for written refusal. It is your right. Without knowing the specifics, I think the manager was just gambling that you might not be bothered to go through the official procedure.
However, since you are back in the UK now, I would contact Scarpa directly, even though it's the responsibility of the shop you bought it from. I have had good results from other respectable brands that way. And if even that does not work - send them back to the shop, with a letter, by registered mail. They still have the legal responsibility to respond to any guarantee claim pretty quickly.
Alas, how Brexit comes into it, I have no idea... (although I guess the customer protection is dependant on purchase in EU country, not on the nationality of the purchaser)
Post edited at 10:09