Some suggestion for preventing fake giveaways

Not to mention that just because someone wants to gift a game, it doesn't mean they want it his or herself.

That could have some "bad" people, just report totally legit giveaways just for fun and cause "chaos", expecially if they don't have enough points to enter... How would you prevent that then?

You didn't think about this.
"Show the paper and black it out"
Yeah sure, I can black out anything you know?
These things just happen and there is no way to make a website 100% idiot-and-retard-proof.

People are being generous, and you just want to make it harder for them, which would turn them off.

There's an option in your profile settings that deals with displaying your gift inventory and is enabled by default:

"Keep your Steam Gift inventory private, regardless of your inventory setting above."

The best way to verify that someone has what they're gifting (in the case of gifts and not keys) would be to force them to disable this option, set their inventory to public, and then check their inventory data when creating a giveaway. This is pretty much how the TF2 raffle site does it, by allowing you to only give away items that are actually in your inventory, and is no hassle to the person creating the giveaway (provided they have no problem with making this information public).

You might also then be able to pull what version of the game it is when scanning their inventory so people who, for example, don't want a foreign version of the game can know exactly what they're getting before they enter a giveaway.

I disagree with this. Sometimes when making a giveaway you only have money/opportunity to buy it at a later date.

This would also force all giveaways to be single handely checked. Terrible idea. The current system for Fake giveaways already works (Report button, lack of gift delivering which results in a ban, etc.)

How about this! I got it! This is an amazing idea...why don't we all read the FAQs, be considerate, have brains....AND NOT MAKE FAKE GIVEAWAYS! Simple!

no offense but i would rather just force users to have a game already located in steam inventory before they are able to create a giveaway for it. This could work just as simple as everytime you lick the create giveaway button you sync your profile with the site. This would cause problems for cd key giveaways, but those are also the ones that are usually not legit and get people into trouble (although more often than not they are good legit giveaways sometimes sacrifices need to be made). I would rather see games only gifted through steam anyway. I see too many illegal cd key giveaways that create a bad name for the site.