"These mechanisms produce behavior that looks like conformity: You are more likely to evaluate an activity positively if others do so. But in these examples your attitude is not directly influenced by hearing about the attitudes of others. Your attitude is only indirectly influenced by others because their behavior exposes you to additional samples of the activity (from Science)."
I thought this was surely studied inside and out because this is what the whole advertisement industry is based on. But obviously we haven't studied it much.