What is a surrogate consumer? Give an example.

Examples may vary.
In addition to everyday consumers who are influential in affecting others' purchase decisions, a class of marketing intermediary called the surrogate consumer is an active player in many categories. A surrogate consumer is a person who is hired to provide input into purchase decisions. Unlike the opinion leader or market maven, the surrogate is usually compensated for this involvement.
Examples: Interior decorators, stockbrokers, professional shoppers, or college consultants can all be thought of as surrogate consumers. Whether or not they actually make the purchase on behalf of the consumer, surrogates' recommendations can be enormously influential. The consumer in essence relinquishes control over several or all decision-making functions, such as information search, evaluation of alternatives, or the actual purchase. For example, a client may commission an interior decorator to redo her house, while a broker may be entrusted to make crucial buy/sell decisions on behalf of investors.