I do not collect the swag they give out at conferences. Swag piles up, taking up space, and at some point in time, we end up throwing this stuff. At the risk of appearing rude, I refuse gifts from people who invite me to give some talk or presentation. And I will never bother you with stuff at a meet or event I organise (unless it is something that you can eat). There was a time when I liked these things, and I would hoard them along with everything else. But then one day Geoffrey Cain took me on a visit to a landfill outside Phnom Penh. After seeing the amount of garbage, I lost my appetite for things.
On a related note, we have to start reducing the garbage we produce.