I never heard of these before, but I'm not shocked.
A 26-year-old airline passenger was arrested for trying to bring a vampire straw through TSA.
www.usatoday.com
It's the same sort of thing that gets popular for awhile, going back to the Kubaton keychain or maybe even the sword-cane. People often like the idea of a self-defense weapon that has a dual purpose, like an ink pen that is hardened and can be put to use as a stabby kind of thing if need be.
Everyone wants the magic device that puts one over on cops and security people. Ha ha, officer, it's not a stabby thing, it's a pen! See? It writes! It's not a stabby thing, it's a straw! See me drink from it! It's not a set of brass knuckles, it's a belt buckle! See it hold my pants up?
The problem is, there is no magic. You're not going to fool anyone or argue a cop out of seeing it for what it is. Wink, wink, doesn't really work.
Weapons are in what they are used for, not necessarily what they look like. There's no way to reliably fool professionals. It might work once or twice; but when you get caught, you're caught.
About the only dual-use self-defense weapon that I think can be carried reliably is a cane, and that's for people who need one and can prove it (typically). At my age, my gait is messed up. If I start walking with a cane (and I have in the past, but I'm better now), I can pretty much take it anywhere; if I have to use it to defend myself, oh well. However, something slightly more offensive in nature, like a sword cane, isn't going to pass. There are lots of places a person can learn to fight with a cane, and lots of canes that can take a lot of abuse. So I'll exempt that.
But otherwise? I've seen people get their Kubatons confiscated, their brass knuckle belt buckles, their 'CIA pens' and their plastic x-ray-proof daggers. You can argue all you like, it's not going to fool a cop.
My suggestion is to leave the vampire straw at home. Good grief.