I never said it was a slap in the face for me personally, I bought the games on sale back in February. If GOG extended their refund window then that would be much more fair to everyone who rushed to buy it before it was delisted. As far as refunds go, I just checked my orders history and I don't see any refund option for those purchases, other than the option to contact support which has always been there, so I wonder why that's the case for me when you say you get a refund option going back several years.
I only paid $6 (Canadian) in total for all of the Syndicate and Underworld titles, so it's not like I was ripped off, but if they're giving it to other people for free as a reward for not buying it when it was originally available, it's an option I'd definitely like to take if I can (or at least to receive some keys for gifting later).
Nor was I assuming you were, which is why I started my sentence with "If...".
Checking my own order history, it looks like they've closed that window now. It might have been accidental that they opened it to include things several years back or it could just be that they opened it for a limited time deliberately. I certainly wouldn't have expected them to leave it open indefinitely.
As for receiving keys, I'm pretty sure you can. I have some gift keys waiting in my account from this very giveaway.