WiFi? WTF?

Every time I go in any store/restaurant/business, my phone always shows that they HAVE a WiFi...but it's locked and you need a password. Why?!? Would it cost them anything to let people use their WiFi? Most restaurants give away water for free and that costs SOMETHING, right? The WiFi doesn't cost anything, right? And how about airports? You have to pay to use their WiFi after you've already paid upwards of a grand to go through their shitty BS security and put up with their lousy $10-an-hour earning, dead-end-career employee's shitty attitudes. The least they can do is flick on the security settings and let you surf the net to take your mind off the fact that your civil liberties are being jizzed all over