A good car now uses less than 5 cents per mile in fuel. Electrics can be entirely powered by the sun as well. A bike rider burns about 10 cents per mile in food costs and is 3 to 10 times as likely to die or be permenantly disabled. All hail the open minded bike riders.
$2.00/gallon, 40 mpg = $0.05/mile so that requires one to drive a very efficient car at current gas prices that haven't been around for years---not just "a good car." Of course, higher mpg's could offset a higher gas price as well, but 40 mpg is still pretty good until one gets into the hybrids (higher purchase cost etc etc).
I bike around 3000 miles per year. My wife and son both bike extensively as well--commuting, errands, and recreation. Our food budget didn't move at all when we started biking and hasn't moved since then either. We just changed what we ate (healthier food choices), where we ate (home), and when we ate (more consistent meals, fewer junky snacks). Our food budget is $125/week for a family of two adults, one teen. We're not training for races. We're riding to work, to the library, or some other place like that.
Does biking require more transportation time? Yes. More patience related to weather? Yes. More diligence during the trip? Depends on the route. More money? Definitely not according to my annual transportation and food spending patterns. And we've moved down to a one-car family, lost about 75 cumulative "family" pounds, relieved stress, and enjoyed the dawns and sunsets.
Safety? Plenty of lights if needed, a smattering of reflective bits, good eyes, and good routes. One near miss at "backing out of the parking space" speed (I was the faster vehicle) in several years, thousands of miles, and three distinct riding styles (middle-aged dad, tentative mom, and daring son). I've had more "near t-bone" intersection misses in my car in the same amount of time from idiots running red lights.
Drive a car if you wish. I do as well when I need to. The notion of cyclists holding up their noses at drivers and drivers pointing fingers at cyclists for personal choices makes no sense. Really it's just one more soapbox that people can jump on in their free time.