Why Some of the Giveaways are 0P

Maybe they're not available for purchase atm, like arkham knight..

because steam api is bugging out and those are prices api return

Arkham Knight is 0 points because it was removed from the Steam store for now. The others are probably a disturbance in the force.

Most of them - Steam API bugging out last 3-4 days
Batman - because it got removed from Steam Store and cg wasn't around yet to manually change it's value in database.

Cause there not avalible to buy on steam.

Letter Quest: Grimm's Journey appears as 0P though it does have a store page and a price ($8). It now "includes original and remastered editions", but does that mean there should be 0 points granted for a giveaway of the original game? It seems a bit unfair...