Victims of fashion.

Some processes employed to attain the "right" look:

Stonewashed jeans are jeans that have been treated to produce a faded, worn appearance. This is usually accomplished either by washing the jeans with pumice in a rotating drum, or also by using chemicals to create the appearance without the use of a rotating drum. Stonewashed jeans were a popular fashion trend in the 1970s.[1] In the 2000s stonewashed jeans were heavily distressed, with pre-made holes, frayed edges and extensive fading caused by sandblasting

The fungus Trichoderma is also commonly used in the process of "stone-washing" jean material. Since the fungus decomposes cellulose with the enzymes that it produces, this allows for the characteristic appearance that the jeans have been washed with a stone.
[edit] Acid Washed jeans

Acid-washed denim is washed with pumice stones and chlorine until it is bleached almost white. The process was invented in Italy by the Rifle jeans company. Acid wash jeans, worn with fringe jackets or the Perfecto motorcycle jacket were popularised by hard rock, outlaw country and heavy metal bands in the 1980s. Skinheads and punk rockers would spatter bleach on their jeans for a similar effect.[2] Acid washed jeans made a comeback in the late 2000s among teenage girls.[3]

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