It can get worse than people snooping on what you're reading ... they can also modify the content. In many places, like at cheap motels or providing free Wifi,

It can get worse than people snooping on what you're reading ... they can also modify the content. In many places, like at cheap motels or providing free Wifi, they inject ads into content pages or other crap. So how do you know if the content you're reading has not been tampered with? You don't, unless the connection is encrypted.