It's Saturday at 7am

So, it's Saturday at 7am. I am sitting here at my computer listening to WNYC and reading a Ron Paul supporter blog, the Daily Paul.

How come six days of the week, when I have to be somewhere in the morning, I can' t drag myself out of bed, but on Saturday morning by 6:45am I feel like I am wasting my time if I haven't gotten up yet?