I point out any issues but still do my best to make whatever I’m selling look and perform the best it can. This can be compared to touching up chipped paint, polishing chrome, polishing all exterior light lenses, cleaning the carpet, etc on vehicles. If you get a chip in a windshield you may have it filled instead of replacing the windshield. I wouldn’t say your covering or hiding this issue. Would you fill a chip on a Ferrari 250 GTO, of course not. If I was selling speakers that were in 250GTO league then a refinish is necessary.
If I have a chip in the veneer of a $500 pair of speakers I’m not going replace the veneer and I’m certainly not going to leave a nasty chip exposing the MDF, this is why you got them cheap in the first place. I’ll stain it to match then show clear pictures of all the areas with issues. I’ve filled areas before with stainable filler then refinished. This area was obvious to the buyer and they were satisfied with the offering as it looked better.
Coming across a pair of JBL Lancer 77’s for instance, that look ok and making them look very good and perform excellent to make a few hundred bucks makes sence without cheating anyone. Nobody wants (barn find) speakers, at least not the end user. I agree with previous post, covering these issues then offering the product as excellent or 100% is shady. I’ve been very successful on eBay selling many pairs of speakers to buyers from Japan to France and in between. I usually get at least a quarter to a third more in revenue compared to the same speakers listed by others. The higher sales price is due to attention to detail and clear well executed pictures, I’ve never had one issue with any offering. Now picking up a set of $500 studio monitors having the talent to turn them into $6000 studio monitors, that I wish I had the ability to do, I’ll leave that to Kenrick the ultimate speaker flipper.