I've never been to a conference and I've never been to a meetup that had swag.
In general, I find the idea problematic, since these conferences tend to cost a lot to go to, and some of that money has to be going to subsidise these pointless trinkets. I'd prefer to get in for an amount of money I can afford instead.
There are meetups and user groups at times that are sponsored. Weekend Code Camps too give fun things away, but obviously not why any of us go. Still, cool to be surprised with a neat giveaway even at the free shows.
I too find the trinkets pretty pointless, but I think their presence in our current economy probably goes towards subsidizing the ticket price. The sponsor pays the venue, say, $25 per attendee to give away the swag that costed somebody $2.50, in theory the net benefit is passed off to the attendee in some way if they don't mind being sold to.
In a few cases, like my treasured, octocat figurine I posted in this thread, it seems like a win-win-win where the trinket isn't pointless. But yeah, this kind of appreciated value is usually lost and the whole effort is wasteful capitalism.
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