People should have some sort of moral compass period and there are a lot here that do not. Some will promote a company scam or not. Like your example 1xbit, there are at least 50 users who ruined their accounts once 1xbit stops advertising for just a few bucks a week. Maybe they're all owned by the same person as suggested by others, maybe not but they're all worthless accounts once 1xbit leaves this forum.
The big question right now is, will 1xbit leave the forum?
They know that they can still lure some newbies here, register in their website, and then scam them. Well, the number decreases as many know that they are a scam site, but I believe that there are still who are getting scammed by this shitty website. Maybe those 1xbit participants are an alt-accounts of a group of people here.
What OP is saying is that, always be careful, and don't promote a scam campaign right?
How can you identify if that campaign is a scam or not? You will never know unless they did it.
I remembered the recent signature campaign which is BetterCaulRaul.it. I mean they've been here for months, gaining he trust of the users, he participants, and even the manager who launched the campaign. They've been here for months, and that's enough for them to gain the trust of people here, only to find out that they ran away alongside the money that they got.
Bottom line is, you will never know that a campaign is a scam unless they'll scam you.