I got cards like that. And just like yours, mine ask for the bomber's name and address too.
Always wanted to say, "I'm sorry sir, but you can't explode until I have your name and address."
I was on the evacuation committee for my work, and we learned a bit about threats. Bomb threats will not automatically evacuate the building. That's because we get 150+ bomb threats a day. Something's really got to stand out for it to be taken seriously.
and ask ALL those questions. apparently more than a few gave their name and address before they realized what they were doing.