Does having a group giveaway mean that people who are not in the group cannot see it?

Playing Appreciated cough

Makes sense. Well, I left my group giveaway and group here in case you want to join that ;3

You were thinking about SteamCompanion or GameMiner maybe, those were big group-bait sites. SG tries to limit people-fishing to this forum category—most likely because we had more than enough of the "join my group of totally legit raffles for $$$100,000k CS:GO skinz" recruitments even in public giveaways already.

That's a good point.

*lowers the frequency, at least.
I've had people beg to get in to my groups. When I asked why they wanted in [when I'd never met them before], they were all 'Oh, I saw you were doing this group giveaway for this game I want- I assumed that was the group it was for. It doesn't matter, just invite me to whatever group has access to the game, okay?'.
Typically, their tone is even more entitled than that.. :X

Given that I've had a half dozen of those interactions by now (and that with my habit of ignoring steam invites unless prompted with a reason to look at them), I'd imagine that if the system was more open, it'd be pretty overwhelming.