I have no idea, but my guess is that Amazon pays something, obviously not the consumer price.
Amazon is the party who is benefitting from Prime subscriptions, after all.

If GOG wanted to give games to users for free, they have their own infrastructure to do that, no need to use Prime services for that.

Then again, it can be seen as a marketing tool for GOG, like GOG Connect used to be.

Well, as a long time Prime member, I like that I get free GOG game codes now, since that to me offsets some of the Prime membership cost increases.

As a kindle eBook reader and KU subscriber, I get a ton of free ebooks or at least a lot that get priced at $0.99 sometimes. I also get some other credits occasionally. (Currently own more than 2500 Kindle eBooks. Damn, I need to find a way to extend my lifespan lol.)

Another reason, is being able to order items that I can get within a few days (sometimes next day or even same day) and not having to pay the shipping costs as a Prime member. It's been a huge benefit during times I couldn't go out or after store hours to get it early next day, etc. (Was a huge benefit in 2020 during Covid.)

There are other benefits, but I'll add one more that makes it very beneficial to me.

This final one is the Prime Video section. There are often deals that happen where you can pay $0.99 per month for 2 or 3 months for some channels.

This has allowed me to occasionally enjoy MAX, HBO and a few other channels at a low price. But since I'm a huge anime fan and have Crunchyroll already, but still I'm missing HiDive. But for the next 2 months, I get to enjoy HiDive on Prime for $0.99 per month thanks to a recent deal offered. Heck yeah! :) (I now get to watch "I Parry Everything" or I think that's what it's called and re-watch Emminence in Shadow.

So yeah, for now the benefits far exceed any demerits for me. So, I'll continue on with my Prime membership.

P.S. Looking at the GOG Amazon thread, it seems there are 2 more GOG codes coming out on July 25th for Cat Quest II and Midnight Fight Express.
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Thank you all. I've just discovered Amazon Gaming and its free codes. It's a shame it took me so long.

I have a code for Hitman Absolution. PM me if you want it.

I fixed it for you.

Speaking of which, GOG codes for Cat Quest II and Midnight Fight Express just became available on Amazon Prime Gaming.

Has there been months without GOG codes inserted in the list?

Just made a Prime account yesterday. How often do they give away GOG codes? Like once every two weeks?

I'm pretty sure In the past there were months without a GOG code on offer. I can't solidly confirm this example, since it's possible a singular bonus dropped without prior advertising/leak, but:
https://www.gog.com/forum/general/amazon_prime_games_and_drm/post95

That same thread sporadically tracked the monthly drops, so you might find other examples.

It can happen. Taking this year as an example, this is how many Amazon Prime GOG codes were given out:
January - 0
February - 1
March - 1
April - 0
May - 3
June - 4
July - 4

There were two in March: Fallout 2 and Fallout Tactics.
Also five in July.

Thank you, I must have missed Fallout Tactics when I looked up the articles about releases (dropped on short notice maybe?) and one of the ones in July.

It's kind of random, some of their codes last a long time which seems to be a way of reducing how many games are given away.

They give away a lot of AAA titles though which is nice to see: https://support.gog.com/hc/en-us/articles/4408064600721-FAQ-Amazon-Prime-x-GOG?product=gog

I hope they do some repeats during dry months though for the ones I missed, lol.

Ah this is useful, nice!

Good to know its being tracked and I can see some months was pretty bad from what some posted. but still not bad value depending if folks like random drops if they are really just dumping on prime for this only...

Oh I agree it's good value, especially if you've already paying for Prime for whatever reason. Not really worth paying for it just for the GOG stuff though. Like all subscriptions and memberships you really need to use the most of what you pay for to obtain full value.