People can just sit back and connect to the public wifi , use packet analyzer like wireshark to monitor each and every data traffic that transmit across the network , Even when you're at home ,you're using your wifi , and your friend come to your house and using your wifi at the same time when you're doing bank transaction,he can capture the data too , it's the matter of whether the data is encrypted or not , as the trifacta says , some website offer SSL encryption , which provide end to end user encryption , mostly bank website would have this service , but still there's already method to decrypt it as there's flaw on this technique , not necessary using home wifi is safe,i can just crack your wifi password,connect to it and wait for you to use it and get what i want,so the safest is using cable,if you really think sometime when you're in airport,you really have the need to connect to your bank account so that you could do some transaction,try subscribe to some good VPN service , it tunnel and encrypt all your data traffic so that hacker don't have the chance to look at your data,for your information,there's a plugin in firefox which could monitor the whole traffic on the same network , if it detect any raw data without encryption,straight it'll capture it and store inside that hacker's pc , so it's not only public wifi could cause your bank account to be stolen , even your home wifi could be too , it's just public wifi is more dangerous , and besides don't ever use public pc to connect your bank account,there might be keylogger inside,and not unifi that could cause this kind of thing to happen,any connection that is wifi would cause this thing to happen,don't you forget how wifi works,it's by using electromagnetic wave,and the wave move in air ,that's mean any data you input is broadcasted in the air,so people can just easily capture it,but cable different,if some would wanted to do somethng with it,they must come to your house,personally connect their laptop to your network with cable,which would cause themselves in jail lol,hope it helps.