Now do Amazon which is a retailer, often running at a loss on the retail side, with a nicely growing Hosting business... but even the margins on the hosting business don't justify Amazon's P/E ratio.

I don't think the market is efficient, it has a lot to do with perception. Amazon, for instance, is constantly doing press releases for products, even products that have no future (this is a deliberate strategy near as I can tell from my time when I worked at Amazon)... while Apple does 3 or 4 product introductions a year, and doesn't do a lot of PR stuff (Though Tim Cook is getting interviewed a lot more than Steve Jobs did.)