Why is it that some people get so self-righteous over things, objects, devices, etc.?

This sort of goes hand-in-hand with a thread we had recently about Macs. Several people pointed out the all-too-frequent mentality of Apple enthusiasts that is nothing short of a superiority complex, just over a silly computer (or phone, or mp3 player, etc) Anyone who even dares speak negatively about their precious “thing” is met with vehemence and nothing less.

What’s the deal with that? Why should people be treated like dirt just because of their choice in meaningless objects? Are these people lacking something in their lives that all they have to cling to are their electronics?