The Price of Air

Some garages still have free compressed air and water for the car, and it is getting fewer and fewer.  Last summer, I saw a caravan in a garage filling up drums of water. 

More recently, we went to a garage and found air to be £1 for 6 minutes.  We can always just use the little compressors, but we like the convenience, but nothing is ever "free".  The electricity to the pump, the annual PSSR inspection, the maintenance and repair of the compressors, etc.  On the other hand, I am surprise why the expensive garages don't provide provide those for free either.