I wasn't looking for actual vendor names, but moreso the marketplaces that this sort of thing is deemed acceptable.  From what I've read DAZ can be quite particular about what gets published but I've not read anything regarding QA at other marketplaces to comment.  One would think that some general conventions around naming and folder structure (and of course if the darn thing even functions) could be added to said QA process, if it exists.  If not, then a non-profit, fan-run governing body could be established to provide an additional "Quality-Approved" certfication to their product.  It would be entirely voluntary for vendors to use obviously but is a little more official than just a white or black list of vendors.  Those vendors that care enough about selling quality products will submit their work for review to gain that certification.  That's the idea anyway.

Again, the better method would be for the marketplaces to add this sort of thing to their own QA checklist, but in the absence of that, perhaps a "Fan Approved" certification that a vendor could tote (even provide a logo for them to add to the product page) would be enough to sway behaviour towards using best practices.