Amazing how some ( PP ) are stuborn .....
Let's say that instead of WiFi of a coffee shop, it is a Bar with music... Obviously, the owners of the bar expect the free music to bring them clients ( same situation as the wifi ).
Now, that music can also be heard in the parking lot of the bar ... You are there with friends ... you hear it, you sing along, you talk about that tune better then that other tune...
Did you commit a crime ??? Did you steal anything ???
Sure, the owner can be pissed that you don't come in ... he just has to put better sound insulation ( way more expensive than having a daily user/pass combination )...
The original law was intented to prevent newbies ( at home ) from having their wifi connection used for spam, phishing, etc ... Also, the newbies can be hit with overages if he has a limited plan ..
The coffe shop owner is supposed to be a busines man, not a newbie.
