My biggest problem with CL is that I always seem to get a lot of replies from Nigerian scammers. It's pretty obvious shit but my sister once facilitated an enormous reshipping scheme. She was even engaged to the fictional person who controlled her. Even when I brought it to her attention, she continued! I showed her that the only photo she had of him was the second most stolen photo used by scammers. No reaction. Eventually, it sunk in and she figured it out. It was sad. Not a reflection on CL so much.
This summer I had a trial partnership with a couple of guys fairly new to me. We would buy up storage units, etc. and resell stuff. Part of their business plan was to be pretending that we were not resalers and to stalking the free section of CL snapping up anything we can make a buck on. I felt it was a violation of the free section's intent to do that. It made me sad that the free section of CL would be negated by a bunch of lying predatory 'entrepeneurs' creating nothing but a profit.
Certainly, there were going to be people who would not care but most (I felt) were more motivated by altruistic motives than they were a desire to rid themselves of something. I felt we should be open about our being resellers. They felt I was an asshole. Somewhat later, one of them pitched the idea that we sell t-shirts with primitive drawings and tell people that the money would help "retarded kids". End of trial partnership.