When sensitive materials became fast enough to enable hand-held exposures, hand cameras became the fashion and to make them less obvious, American makers started to have them covered in black leather, with metal parts finished in black. Remnants of this approach can still be seen nowadays with cameras partially covered in leather.

Anyway, this tradition carried on when smaller format cameras became viable: even during the earlier days of 35mm photography, both early Leica and Contax cameras were finished likewise, with metal parts finished in black.

It was when nickel plating became economical enough that larger camera parts started to be bright finished, and later on, when chrome plating became affordable as an industrial process, the use of this harder-wearing finish became wide-spread: camera then acquired the connoctation of "male jewellery".

Sure enough, with modern manufacturing techniques and materials, black cameras are actually cheaper to produce: the plastics materials can be of solid black colour so that no extra finishing would be required to make a black-bodied camera. In that sense, a "chrome-finish" camera would cost more to make, and of course, many plastics-bodied cameras with applied chrome finish can look pretty tatty after a while as the surface coating gets rubbed off.

For me, black cameras remain a more viable option for my style of 35mm photographic work for being less conspicuous.