I have a theory that advertising and brand messages can evoke the oxytocin response in us humans. This hasn't been validated by science yet, but it makes sense. Sociologists talk about parasocial relationships, that is, relationships with people we haven't actually met, such as celebrities or fictional characters.
Fans express their desire and love for characters in TV shows in the same way as they might talk about a real person, and they sometimes cry real tears over fictional events. So why would their love be less real -- or less oxytocin-producing?
I ran across this December 2008 article in Science Daily that provides another piece of evidence. Vanitha Swaminathan, Karen M. Stilley (University of Pittsburgh), and Rohini Ahluwalia (University of Minnesota) found that someone's attachment style influenced their reactions to brands.
The kind of bond we have with our mother -- the way our oxytocin response forms -- depends on how she treats us. We then tend to apply the mode of loving we learned from her to our future relationships. Psychologists group them into three or four "attachment styles."
From the article:
According to the authors, anxiously attached individuals are more influenced by "brand personalities," the idea that a brand possesses humanlike traits, such as sincerity or excitement. "Because of a low view of self, anxious individuals use brands to signal their ideal self-concept to future relationship partners and therefore focus more on the personality of the brand," the authors write.
What this says to me indirectly is that our attachment to a brand uses the same brain circuits and neurochemistry as our attachment to another human. So brand loyalty is a kind of love that's as real as any other.