[chaorace]

I'm speaking in the context of the parent conversation ("unencrypted WiFi packets"). On wireless networks, all devices share the same "wire", so to speak. Normally that traffic is useless when captured due to encryption, but that's not the case on unencrypted (i.e. public) WiFi.

[Control8894]

It doesn't matter if the wifi is encrypted or not. All that matters is that you share the network with an attacker. You can ARP poison just fine, encrypted or open, wifi or wired.

[chaorace]

Well, actually... you can only successfully launch an ARP poisoning attack if you're on the same network segment as the impersonated host.

(Yes, I am indeed being pedantic on purpose to prove a point. I offer this parenthetical to you in place of an apology)