They even have a non-free option that eliminates the VPN as a proxy feature.
"Hola built a peer to peer overlay network for HTTP, which securely routes the sites you choose through other Hola users' devices and not through expensive servers. Hola never takes up valuable resources from these users, since it only uses a user as a proxy if that users' device is completely idle (meaning device is connected to electric power (not on battery), no mouse or keyboard activity is detected, and device is connected to the local network or Wifi (not on cellular)). This makes Hola the first VPN service without underlying operational costs. Although Hola doesn�t need to pay for bandwidth, we still need to pay the engineers who create, maintain and keep improving the free Hola service. Hola generates revenue by selling a commercial version of the Hola VPN service to businesses (through our Luminati brand). This is what allows us to keep Hola free for our users. Users who want to enjoy the Hola network without contributing their idle resources can do so by joining the Hola premium service for $5 per month (or $45 per year)."
They even have a non-free option that eliminates the VPN as a proxy feature.
"Hola built a peer to peer overlay network for HTTP, which securely routes the sites you choose through other Hola users' devices and not through expensive servers. Hola never takes up valuable resources from these users, since it only uses a user as a proxy if that users' device is completely idle (meaning device is connected to electric power (not on battery), no mouse or keyboard activity is detected, and device is connected to the local network or Wifi (not on cellular)). This makes Hola the first VPN service without underlying operational costs. Although Hola doesn�t need to pay for bandwidth, we still need to pay the engineers who create, maintain and keep improving the free Hola service. Hola generates revenue by selling a commercial version of the Hola VPN service to businesses (through our Luminati brand). This is what allows us to keep Hola free for our users. Users who want to enjoy the Hola network without contributing their idle resources can do so by joining the Hola premium service for $5 per month (or $45 per year)."