1) You need a device that can connect to wifi
2) Approach your neighbor/shop owner/coffee owner
3) Ask: "Can I connect to your wifi, please?"
4) It takes about 4-5 seconds to get the password to the ssid
5) Works on WPA2, WPA / TKIP/AES and WEP
6) Success rate: 70-80%
Cheers
Public, municipality-sponsored Wi-Fi is usually a joke (slow, non functioning, requiring you to like a certain facebook page or follow a twitter account, etc.)
In Greece I suggest trying the business' phone number, you can find it on discarded receipts on the ground or on tables.
It's always worth it to try and snoop the password hanging by the counter.
Other good combos are companynamewifi, wirelesscompanyname, wireless, internet, internet123.
t. scrooge that never wastes money on mobile internet subscription and survives on leeched public Wi-Fi
Also when I see NLP, my first thought is Neuro-Linguistic Programming (https://en.m.wikipedia.org/wiki/Neuro-linguistic_programming) , not Natural Language Processing.