Not all gliding operations use tows. Winches are also an option. They're cheaper too but they are more limited in launch altitude. There's other more dangerous

Not all gliding operations use tows. Winches are also an option. They're cheaper too but they are more limited in launch altitude. There's other more dangerous things about gliding too, like the way gliders tend to bunch together circling to take advantage of thermals and get close to mountains to enjoy the updrafts there. So mid air collisions and controlled flight into terrain are more common. But overall I'm pretty sure it's still a safer sport. But I have to admit I don't have stats either.