The phrase "highway robbery" means an unfair or excessively expensive cost for something, just like how thieves used to rob travelers on the road a long time ago. Full definition
Throughout the history of our country we have seen property ownership change hands through the force of war, racism and actions that have been nothing short of highway robbery. (remonline.com)
At 15 cents per MB — highway robbery by any standard — it wouldn't take many images to grab all an author's royalties, leaving him with nothing. (bergsland.org)
He probably could have had him for highway robbery fee from Celtic with timely action. (justarsenal.com)