Summary: Everything listed in this thread.
Am I really hostile, or am I just conditioned to become so because I live in a town riddled with morons as well?
I am however one of those who bike on sidewalks, but only for a semi-rational set of reasons:
1) Traffic, where I live, tends to get rather scary; even in broad daylight. Bike lane or not, I'm not going near anyone that drives a car when I go biking. They tend to not pay attention to their surroundings, be it driving 15-under speed limit for miles on end, or taking up all lanes because they're too distracted with all the pretty greyish-tan/beige buildings that take up much of the street.
2) Sidewalks provide shortcuts if you can find any
3) People don't walk on the sidewalks half as much as you'd expect around town these days (usually because the beach is right there).
4) Sidewalks, if you map them out properly, and take advantage of some landscape, makes for good racetracks; especially if you must stay within the cement, and it has plenty of corners.
EDIT:
And to contribute-- No matter how early and ready I get for work, even being ready/leaving 15-minutes early; I'm always 5 minutes late. Similar case with church (and arriving there much later, usually halfway late), but that's either due to family taking their sweet time getting ready, or every conceivable parking spot at church is taken by snowbirds or "mandatory" church-goers that only come for certain holidays to remain "official" Christian/Catholics. If you're not going to be honest about your virtues or anything regarding religion, then be an Athiest; stop making the rest of us look like chumps.