Question about P on giveaways

Hi all!

I have a little question about P on giveaways.

As the FAQ says, the P on a giveaway is based on the price on Steam. So, how some giveaways can have 50P if the game on Steam is $19.99?

Also, some giveaways are on 60P and, when I follow the link to Steam, I see something like:
Game $19.99
Your price: $59.99
Yes!!, the "pack" is more expensive than the game itself. And the pack only have the game and nothing more.

All of this, is legal? It is a bug on SG? Is perfectly fine?

Thanks a lot
Regards Juan Pablo from Argentina