I think I realize now why Apple users look at Microsoft users like they are nuts, and why Microsoft users look at Apple users like they are arrogant. It occurred to me over lunch. Let's look at Mac OSX and Windows Vista as an example.
Say Consumer A wants to buy an operating system for their Mac. They go into the Apple store, pick up a copy of OSX, and hand their credit card to the clerk. Nothing impedes the transaction. They even take a step further by bringing the check-out to you at the Apple store.
Say Consumer B Wants to buy an operating system for their PC. They go into a computer store, and... they see 7 flavors of Vista. Whatever reptilian emotion was driving that purchase has now given way to intellect. Nothing could be more destructive to the emotion-driven consumer. The pause necessary to pick which version is right for you can lead to all sorts of internal conflict, which in turn gets in the way of the transaction.
Now, I can accept that Microsoft may be attempting to make Vista more "attainable" to lower budget consumers by creating different gradations of their product. However, if they want their consumers to be singing the praises of Vista, they need to get them out of the store as quickly as possible. Nothing kills the mood like trying to make a purchasing decision under the advisement of a BestBuy employee.
If you are an Apple guy, you are looking on with a smirk on your face, as you watch the Microsoft guy standing in a state of confusion. If you are the Microsoft guy, you are wondering why that Apple guy is staring at you as he's walking out of the mall.