I just don't get it: what's the point of a discount offer where you get the best deal only if you buy several versions of the very same game? I.e. you need to buy the Standard, Deluxe and Gold edition of the same game, not even counting the DLCs and upgrades you need to buy twice or more.
This is ridiculous.I'd wish GOG would concentrate on offering good deals instead of such fake discount nonsense.

it's actually poor managing of the site. You see, some editions can't technically be closed off the purchase due to oversight of staff, but they are not encouraging you to buy twice same games... They just rely too much on common sense of customers not to buy same editions twice, but in reality, people think this is encouragement to spend more.