Travis, I don't know where you live, but here in the real world, just about everywhere is potentially dangerous. If it isn't the possibility of being mugged in the city, it's the possibility of being attacked by an animal in the country. Adults realize this, and take personal protection and awareness of their surroundings accordingly.
As far as Craigslist being a hotbed of vice and prostitution, nothing could be further from the truth. Maybe if you would click out of the adult section and get your hand off your dick you would notice a bunch of other sections geared toward buying and selling a whole host of other things (personally, I've bought two saws, a GPS receiver, and a refrigerator from very nice people on there).
If you are seeing vice everywhere, it isn't the CL's fault, buddy.