In order to compete with the likes of the chain coffee shops and now fast food joints, just about every coffee shop or small restaurant is supplying its clients with free WiFi. Unfortunately, there are people who don’t understand the rules of life as far as “give and take” in that you’ve got to give a little to get a little; they, unfortunately just take. They’re WiFi-sucking vampires who have no class and sit there for five hours and buy nothing.
http://robertsiciliano.com/blog/2013/10/22/5-rules-for-using-coffee-shop-wifi/