Well, I set up my wifi with a guest account on open wifi a bunch of times when I had a party on, or when neighbours moved in/out and needed temporary access, just to have the average Joe/Jane not nagging me for passwords. I know. Lazy. I frankly don't care in those situations they are open to packet capturing, as I'm not their brother's keeper. Just don't do your banking on it if you are paranoid.
My own WPA2 secured wifi also is set up for MAC filtering. So only "authorised" users can get on it. Unless of course a real savvy user comes along and breaks through the defenses, but then what chance would I have anyways? The MAC filtering was a remnant from when I had to use open wifi as some peripherals didn't play well with wep/wap (stupid printer, and a security camera (really!!) ).
And cats are vermin, not cute and not funny, and think they are the boss. Like real bosses really.