That's my reasoning when I buy a new computer. I can buy a MBP for $2000, use it for 3 years and sell it used for $1000. $30 a month is a bargain considering I use it between 5-10 hours a day. I may pay a mac a little more (20%?) than the competition but it's worth it considering it's subjectively better (and objectively different, Mac OS / design / size -- arguably less and less so).
However, I'd never buy an iphone (or an expensive smartphone). Iphone users may disagree, but for what I've seen they provide almost the same experience as much cheaper phones (typically two times cheaper). Another issue I have with the price is that I don't feel confortable walking around with such a small expensive item. So easy to lose it or forget it.