your missing the point you can do that with the hide function, so why would it matter if they made all apps close with the x.
You're missing the point. There's a big difference between "hiding" and "closing" a window. It just happens that these two actions get confusing with an application like iTunes, which is the one you're talking about.
With most applications, closing the window means you lose the content that window held, and are done with it, i.e. closing a document in Pages or Word means you're done with it and it's gone until you open it again, or closing a Safari of Firefox window means you're done viewing those web pages. The reason it doesn't close the application, too, is what if I want to use it again very soon, but I'm done with that particular content? I don't want to remember to leave a document open in Pages or Word or always have a photo open in Photoshop if I'm not using it, but might want to return to the application soon. Say I'm editing photo 1 in Photoshop, then I finish. I close photo 1 and take a break for lunch. I don't close Photoshop however, and after lunch I come back, open photo 2 and continue editing. If Photoshop closed, I'd have to wait for it to open again simply because I closed photo 1, but I'm not done with Photo shop.
Hiding on the other hand, means you do
not lose the content. I have a document open in Pages and hide it, to look up something in Safari: the Pages document
stays open. When I'm finished looking something up in Safari, I go back to my Pages document that I'm working on. It would be quite annoying if hiding meant I have to reopen the document as if I had closed it. Hiding an application is
nothing like closing the window.
...except with iTunes. iTunes is an exception in this case, because there's really only one window that can ever be brought up, and it displays the exact same content each time. That's why with iTunes closing the window is practically the same as hiding it. With other applications, hiding saves your content, and closing means you're done with the content. With iTunes, there's only one set of possible content that comes back each time, so it seems like closing=hiding. Furthermore, the reason iTunes stays open when you close the window is that it retains functionality after the window closes--if you had to keep the iTunes window open to play music, it would be pretty useless. You could argue that you should just hide the window instead of closing it, and then closing it would quit iTunes, but this would be inconsistent. And since when is there anything wrong with having two ways of doing something?