You've had your badge stolen at con? Or before? Either way, that is low. Who would do that? It's not like they could use it, or sell it...or really do anything with it.
Stolen at con twice so that's why i keep with the lanyard it hasn't gotten stolen when I have had it.
I'm just really REALLY paranoid that my clip badge holder is going to fall off and be lost forever. especially somewhere outside the con space.
If it does fall off, please come see the Lost & Found people. In general, your fellow attendees are so conscientious that we usually have
stacks of boxes of stuff left over every year. Seriously.
Try hanging out with the L&F people for a little while during con, and you'll see a steady stream of people coming in all day... because they really care about their fellow attendees and want to make sure someone's driver's license, expensive camera, badge, important memorabilia, new iPhone, etc doesn't get lost. If it gets dropped as opposed to being yanked off and stolen, it's almost sure to be turned in.
I personally don't like the clip badge to cosplay for myself because my badge has been yanked off and stolen. So a tighter more secure lanyard might be best.
I'm really sorry to hear this has happened to you. If you want to bring in your own lanyard, please do so - the only thing we really care about is that people keep the badge's face easily visible at all times (except during photos, of course).
If a line is really crowded and people have to stop and rummage around for a badge, it holds things up. So it makes the yojimbo's lives much easier if a lanyard makes someone feel more secure that they can keep their badge out without accidentally dropping it or having it yanked off and stolen.