Consumers dislike "crippleware," a common practice of manufacturers of removing or degrading features in existing products, a U.S. study says.

"Product versioning -- the manufacturing strategy of deliberate subtraction of functionality from a product --is typically achieved when a firm starts with an existing product and produces a lower-quality or reduced-feature configuration," the researchers said in a study published in the Journal of Consumer Reports.

Many global brands, including Sony, BMW, Intel, Microsoft, Verizon, Motorola, Canon, Sharp and Apple, have employed such "versioning," but when information on manufacturing practices can be easily disseminated via social media, consumers often react with anger to what they see as an unfair practice, the researchers said.

Consumer advocates, bloggers and journalists have been using less-than-flattering terms to describe the versioning production method, calling it "crippleware," "product sabotage" and "damaged goods," the researchers said, giving as an example Apple's removing iPhone features to create the iPod Touch.

Consumers often perceive the removal of a product's bells and whistles as unfair and may avoid purchasing the neutered products that are similar to their superior counterparts, even at lower prices, the study found.

"Products with identical characteristics and features were perceived as more unfair and unethical, and preferred less, when their manufacture involved degrading a superior configuration compared to when it involved enhancing an inferior configuration, or when no information about the production method was provided," the researchers said.