I have asked this question to many, many people and no one appears to know the answer. I have bought and sold quite a few items, and only had one bad experience(500 bucks worth) though.
There are no fees to post, and no advertisements, so where do they make a profit?
I hate to see dogs listed, but it is very common. Here is a current post running in my area.
Do you have a problem with this post, just curious?
Take care all, John Lodi
http://sacramento.craigslist.org/spo/1902944245.html
Craigslist.org charges for listing jobs and properties in select markets across the country. In a nutshell, that's how they keep the sites up and running. I bought my dog box (and other stuff) off of CL. Listing dogs for sale or for breeding in any capacity is a violation of Craigslist's Terms of Service. Click on "Prohibited" any time you see one of those ads.
"Partial list of items for sale and services the advertisement of which is not permitted on craigslist:
Obscene material or child pornography.
Offer or solicitation of illegal prostitution.
Weapons and related items, including but not limited to firearms, disguised, undetectable or switchblade knives, martial arts weapons, scopes, silencers, ammunition, ammunition magazines, BB guns, tear gas or stun guns.
Items issued to United States Armed Forces that have not been disposed of in accordance with Department of Defense demilitarization policies.
Fireworks, including but not limited to "safe and sane" fireworks or any destructive devices or explosives.
Controlled substances or illegal drugs, substances and items used to manufacture controlled substances and drug paraphernalia.
Alcohol or tobacco products.
Prescription drugs and medical devices, including but not limited to prescription or contact lenses, defibrillators, hypodermic needles or hearing aids.
Nonprescription drugs that make false or misleading treatment claims or treatment claims that require FDA approval.
Blood, bodily fluids or body parts.
Household pets of any kind including but not limited to dogs, cats, primates, cage birds, rodents, reptiles, amphibians, fish. Re-homing with small adoption fee OK
Pet animal parts, blood, or fluids - including but not limited to stud/breeding service"