A few things - "have a magical day" is considered unoriginal and insinscere and thus it was asked of the cast to discontinue using it, they're actually required to use original and catered closings in conversation to show they were actually listening to what you said.
I suppose cliche and what everyone else heard was prefered, this makes sense considering most folks feel someone, somewhere, is getting better service and since they're not getting the "special" its ruining their vacation.
Second, CMs are human beings. I'm sure you talk with your co-workers, and i'm sure you discuss all aspects of your life. I'm more than positive you don't always speak proper english and you don't use the cleanest language either.
Mimi, you've got 29 posts - suggesting that your interest in a site like this one is new, probably jsut prior to this last trip. Here you can read the exploits of Disney World in minute detail, you can become informed in the workings, and know what the standards actually are. For example, how many people would know about towel animals if not for sites like this?
With that in mind - we've got a dissapointed thread about not gettign a towel animals.
The point being, Disney does lots of stuff that is above and beyond - but they honestly don't do it for everyone all of the time. They pick and choose, it's all discretionary and rarely is more than dumb luck. However, with the popularity of communication, people get the feeling that they "need" that special act or treatment for their trip. Further examples being the multiple requests we've had here for information about how to be picked for a parade marshall position, or how to be the guest of the day.
People find out about something special, a simple act done for one person, and begin to demand it. There was no mandate to wish anyone a magical day - it grew from one specialized greeting into an expectation, which the company has made a noticeable attempt to remove.
Disney really tries to make magic for people - they do it every day. However, good intention is never much of a match for humanity and the general public. By definition, everyone cannot be "special" or as Dash says in the Incredibles: "Saying everyone is special is just another way of saying no one is."
Minus your knowledge of Disney's actions from boards like these, you'd probably have far fewer expectations. Things not happening wouldn't dampen your day. You wont be plagued by the fear that someone, somewhere, is getting better treatment than yourself. In short, you might enjoy yourself more.
Imagine, just for a moment: Entering the park, seeing the castle - not desiring to enter it at 7am and eating with princesses because you've been told it's the most magical thing ever - and enjoying the real magic of Disney. The part everyone does "get." That's what makes it special.