Abstract art, Roussillon

There is an art gallery across the street from these paintings. There are always paintings hung on this wall if it's good weather. About ten years ago there was a very nice piece hung out and I stopped to photograph. There was a furious banging on the glass of the gallery, made by the owner, yelling at me to stop taking pictures, in a public place, of his painting. I waved and walked on. Every year since I have stopped and pretended to take a snap. I think he gave up last year. I just never understood why he hangs here and then defends the paintings like a rabid dog.