Being a face in a crowd is far more anonymous than being an electronically trackable ID tag with your name and other personal information associated with it.
Unless other people know who you are beforehand, their being able to see your face doesn’t tell them much about you - and that doesn’t even take into account the common practice of costumery and mask wearing at cons. Meanwhile, an electronic badge can be read by anyone with the proper gear, and any relevant information on that badge becomes available to them. Unlike your face, the badge could easily contain your name and other information which is easily accessed without your consent. You could not choose to withold your identity, as you can in person.
I’m not sure how this should be handled. Short of making sure the electronic badges possess no identifying personal information to snoop on, the only option that comes to mind is personal area jammers, making it impossible to read to the RFID at anything except extremely close range.
