Gudauri green runs

I was wondering if groomers actualy use snow cannons ? 

Every single run has rock and grass on them.

I saw at least 10 people fall pecause they hit the rock and go out of balance 

Why are we paying for ski passes if resort doesnt do anything ? 

There is no enough water to use snow cannons. If they would be started, you had no shower.

and why they can't bring snow to the slopes from other places, and then repar whose green marks?

This is a national flavor. If you feel sorry for the skis, there is a very inexpensive rental and repair service.