I'm sorry, but you are just missing the point here. Apple advertises OS X as "having everything". They ridicule PC's that ship with crippled software or "trialware". Yet Apple is doing the exact same thing.
Quicktime is not trialware. The decision to indicate which features you
could have by paying is certainly a questionable practice, but it is neither crippled nor a demo. It is the evolution of Quicktime Player, a media player. Full stop.
The claim that any computer ships with "everything" is not only obviously an exaggeration, but it's also not been made. Apple specifically advertises that it has everything you need to get started. That does not mean, nor does any reasonable person expect it to, that it comes with every conceivable piece of software to perform every conceivable need.
Macs come with a wide array of applications to get you started doing the things you probably want to do with your computer--music, photos, video, making DVDs, surfing the web, even basic word processing. These aren't demos, trial software, or limited versions. Unless, that is, you consider Final Cut Express to be a "limited version" of Final Cut Pro as opposed to two products serving two different markets.
I wouldn't consider Photoshop Elements a limited version of Photoshop any more than I'd call MS Paint a limited version of Photoshop.
Why should it "increase the price of OS X"? It's already there, you just pay for few bits that enable few missing features. And the price is quite tiny, they might as well not ask for any.
All costs get passed on to customers. There is no free lunch. If they charge for it now, and stop charging for it tomorrow, it's because they've made that money up somewhere else. They'll try to pawn it off as a "more for less" move in marketing, but there is no such thing in business.
The "but not everyone needs those extra features"-argument is totally, 100% irrelevant.
Really? So all Macs should come stuffed to the gills with Final Cut Studio and every possible expansion pack for GarageBand? Quicktime and Quicktime Pro are two different products entirely. All "the bits" are already there because the technology is built into the OS for its own internal use.
It's not any different from processor manufacturers using partially defective units for budget lines or even deactivating portions of perfectly good units to sell as lesser products. It's easier and cheaper to build it as a single unit and disable what you're not selling than to maintain separate products entirely.
If you have any use for QT's Pro features, $30 is more than reasonable. As a media player, apart from the full-screen nonsense, it is completely full-featured.