Police regard wi-fi freeloading as a serious offence because IT intruders can download illegal pornography or hide their tracks when accessing sites that promote terrorism, without fear of being caught. The investigation trail invariably leads to the owner of the wi-fi connection, not the piggy-backing surfer.
In the US the first prosecution for wi-fi piggybacking occurred in 2005 when police arrested Benjamin Smith III in Florida. Later in the same year in the UK Gregory Straszkiewicz was fined £500 and given a 12-month conditional discharge after using a laptop to piggyback a residential wi-fi from his car in London. There have been ten subsequent arrests in the UK.