Pretty good troll effort by OP.
There is no one single reason why someone buys anything.
Apple have probably got their variables used in calculating price elasticity down exact. This is why they charge the premium they do.
Price elasticity of demand - Wikipedia, the free encyclopedia
Apple keeps their pricing pretty static, most of the time they're apt to release a new product with varying (or less) degrees of features instead of dropping their existing inventory price to catch people in the demand curve without having to lower their price and risk eroding their brand. Lately they have strayed from this strategy, now selling the iPad 2, iPhone 4S and last gen model of iPod touch at a small discount over the newest models. If they continue doing this it will be pretty clear they have found the tradeoff worth it, although in the long run it will probably damage their reputation, then again they could be doing it to compete with their existing customers trying to sell their old equipment in the hope of upgrading to the newest.
Anyway, by keeping their retail prices high they ensure higher margins, and create a perception of value which generally does not exist outside their computer ecosystem. Their competitors are often competing with platforms having the same parity of hardware and software specifications with each other. Apple have a competitive advantage over them in that that their operating system will not officially run outside of their own hardware, so their competitors can't as easily be compared since they run a different operating system.
Apple may not be the first to release a new feature or product, but they're large enough of a company that if they introduce it before their biggest competitors they gain First-mover advantage.
So, to answer why people buy Apple products, IMO it is because people genuinely like the interface and features Apple introduce to them and because Apple tries not to discount their products too much before being replaced there is a strong perception in value, reinforced by their higher price. Of course, there are some who just follow the herd, all the more power to them; every business loves herd mentality and each company has their own herd.
If you want to see an example of Price Elasticity in action, fix someone's computer for free or near free. Many times the person who got the free repair will question the quality of work you deliver and treat you the same as a shade-tree mechanic, and any suggestion you give them to keep their rig running will be ignored. Not all the time of course, but I'm sure anyone who does IT has experienced this.
It probably does not help that many shade-tree IT people resort to warez because the cost of including retail/OEM software would leave home built computers at a disadvantage over HP, Dell, Acer, etc...