Again, people make mistakes, so they may think the firewall is on, but that one time 3 weeks ago when they were debugging something and they turned off the firewall for it, yeah, we never got around to enabling it again.
Also, my home network is a lot more secure by default than shared public WiFi. At home I have decent control over who and what connects. Sure, people could in theory crack my WiFi password, but the risk of that is low compared to sitting on public WiFi.
