The vendor program is certainly not perfect. I've said that from the start. In fact the impossibility of creating a perfect program is a big reason I resisted doing it well past the time when virtually every other forum had gone to that model.
The reason I finally implemented it as I did was to deal with the fly-by-night vendors, many of whom were these "cottage vendors" who I think mostly had good intentions but often seemed to get in over their head and then just vanish and leave people hanging. A lot of site members got burned by this.
I knew it was going to be a bad system for the good cottage vendors, but I don't have a good way to screen the good from the bad ahead of time so I don't know how to solve that.
The system has definitely been extremely effective at discouraging bad vendors. Issues that kept recurring every few months before have gone to nearly zero since this system went into effect. And the mid-to-large size vendors seem to continue to have good results. But that has been at the expense of "collateral damage" to a number of good small vendors.
As discussed years ago when this system first went into action, and as newer members may be unaware, I am open to considering ideas of how to improve it for small vendors as long as it outlines a clear and easily manageable way to draw the distinction.
For example with Ferrarichat example given, their site just says they have one classifed section for individuals only (with a paid subscription required to post) and a commercial classified section for "sponsors, businesses, or high volume users" which I assume requires some level of sponsorship. So do they actually allow low-volume commercial ads in the individual section? Or do they have a low-volume commercial sponsorship level, and how do they differentiate the levels?