Lets give an example. And it may have happened before, whether
local or overseas.
An owner of a wireless broadband leaves his network unsecured,
thinking that he should be generous (or foolish enough) to let
someone else use his network.
Another guy founds the network, happily connect to it and start
download copyrighted songs and movies.
A couple of days later, police arrives at the poor owner's doorstep
and accused him of downloading copyrighted materials. He is sent to
jail and fined heavily...
So if you are the one leeching, don't give trouble, and if your the
one sharing, SECURE YOUR NETWORK