Why add contributor level to a giveaway?

You don't earn anything yourself from it (outside of the normal CV you'd earn). It's to reward other contributors with better odds of winning.

I use it to filter out people using auto-join bots as I'd rather someone who actually uses the site to win any games I give away. Don't care if they use it to farm or whatever, just. Want a person, not the luck of the bot. And there's a lot of level 0s and level 1s in particular who use them despite the rule change, so: contributor level in effect.

Choosing higher levels is good for your mental health (if you check your winner on SGTools). When you have sent in the 6th reroll request for the same level 1 GA you will know.

Higher level usually means that the key is redeemed faster and you don't have to wait a week to get your GA slots back. Plus what the others said about bots/autojoins/rerolls.

When I see my GA go to someone with 10,000 wins and no games given away, it doesn't exactly feel good

I make all my GAs for lvl1 because I think everyone should have given away at least one game.
Adding a contributor level is not something you do for yourself, it's just a matter of choosing who you want to give your game to, and sometimes one can feel like giving something away to the people who contribute the most.
Also, as a person who regularly enters GAs, I much prefer when there are fewer entries so I also try to make GAs that will get fewer entries so that the people who enter have more luck !

Levels help reward contributors, but they aren't very flexible. For example, you will still get entries from people who only gave to private groups. It's up to you to decide if this is something that bothers you. If it is, there are way to solve it and target only those who give publicly, e.g. using SGTools filters.

Personally I prefer using Level 0 (83% of the giveaways I created are Level 0), but I do use this forum to link to most of them. I think it's more effective against auto-join scripts than high-level public GAs. In addition, forum-linked GAs also tend to get more meaningful comments from people who enter, which I appreciate.

Why not because it's up to the individual giveaway creator to set up his or her giveaway rules and a CV level is one of those rules that can by used or not.

First on lvl 2+, open for all, GA's are the most of the bots, autojoiners and extreme leechers avoided. On lvl 1 you have millions of them (1 GA made in 3 years+ ... easy to see that it is done only for the better leeching chances after that).
When you use sgtools to protect the GA and set that link in a forum thread you have the best chances to avoid 90% of the not so nice people (that make mostly much work and not much fun) and meet a lot of nice people :o)

A bit more work at the beginning but after the win much lesser AND you have much faster the recieved hook (points to level up, your GA slot back and so on...).

In Short:
All "free for all" unter lvl2+ (not protected from a Forum thread or sgtools) is only BOT FODDER (wasted from my line of sight)

Well, don't! There's no reason to add a contributor level restriction. If you want to stop bots from joining your giveaways, then just create a private giveaway hidden behind a puzzle.

+1 for puzzle.

It's more work but I really really like all the people that put time and effort into making puzzles and events to hide GA's...it means whoever entered either really liked puzzles or wanted the game enough to put a bit more effort into trying to get it.

Over a third of my GA's are invite only/on the forums (highest of any personal catagory)
If you make it easy enough it can just be a kinda filter to make it easier for someone who likes the same games or the same music or some other random problem. and if you make it hard enough you can reward people for more effort.

That being said at the end of the day how you give away is based upon what you care about.
If all you want to do is increase your level restrictions don't matter.

you get less entries.
you give back to users that made giveaways.

there are more reasons but they are only valid for some people. ^^

why should I limit my giveaway by level?

first of all it's not about should you do it, it's more like do you want to limit your giveaway by level
as of now I assume you understood that people get levels from creating GAs, so maybe you should ask question like "how much does this game worth? is it okay if I gave it away to ✕ level person?"

Does that improve anything in the score? I earn more level?

nope and nope, the points (CV) you earn is from how much the items you were given away (GAs) worth in price/value

my thinking is "the more people, the better," isn't ? hahahah

there's nothing wrong with what you think because no opinion is wrong nor right,
you don't have to set the CV level to a certain value and no one is allowed to told/force you to set your GAs' level

be lvl 1 contributor = spend like 0.15$ so why i should giveaway my game to lvl 0 contributor when they aren't nice person how to spend 0.15$ to make another guy happy?

no thx, lvl 0 are a cancer xD

i usually set my levels as:
decent game 3+
eh 2+
1+ for crappy games so it will get at least 5 entries for sure lol

To motivate 0 to give something so he/she can be 1.
To motivate 1 to give few more to be 2..
To motivate 2 to give more to be 3..
etc

Over time I have away to higher levels. I just felt like giving back to them.

Er... A lot of the time I make my giveaways level 2 or below... to... fish... for rule breakers
.. Then got really annoyed because they weren't a rule breaker but were a trader with a billion +rep but gave no games on SG ;-;