No password means no encryption over WiFi. So the question that remains is how any data, if at all, was transferred over said WiFi; and what kind of services/ports were open on the systems.
If the transfer of data was encrypted using VPN/HTTPS/TLS or anything, and also using decent set of standards, only then your argument (and you did mention that part) is fully correct. But that question goes rather conveniently unanswered.
My POV: The issue here isn't about WiFi being secure or not. But you should immediately start asking why WiFi was even allowed in this case. Go to any security event such as DefCon and you'll know why visitors disable their WiFi.
Edit: I'm also wondering right now if they were using channel isolation. Ever connected to WiFi in a hotel and seen someone else's Chromecast? I have, and that basically means you can view what someone else is watching. (And so much more)
No password means no encryption over WiFi. So the question that remains is how any data, if at all, was transferred over said WiFi; and what kind of services/ports were open on the systems. If the transfer of data was encrypted using VPN/HTTPS/TLS or anything, and also using decent set of standards, only then your argument (and you did mention that part) is fully correct. But that question goes rather conveniently unanswered.
My POV: The issue here isn't about WiFi being secure or not. But you should immediately start asking why WiFi was even allowed in this case. Go to any security event such as DefCon and you'll know why visitors disable their WiFi.
Edit: I'm also wondering right now if they were using channel isolation. Ever connected to WiFi in a hotel and seen someone else's Chromecast? I have, and that basically means you can view what someone else is watching. (And so much more)