Design trends or sales strategy?

I always received the newsletters from ASID which had many articles talking about kitchen design trends or green design trends…etc, for me, they are just bunches of companies trying to sell their products. Kitchen companies sell contemporary Minimalist kitchen cabinets detect Minimalist design trend is in. Furniture companies sell traditional style furniture say the traditional style trend is coming back and on the rise. The paint companies say the certain color trends will be popular the next coming season which the paint company happens to be the only one sells those colors they claimed to be in style. mmm…I wonder why?