Way back last April, I found that Meike Heston had left a full perm, free version of her excellent Hug & Kiss 2.0 "hugger" HUD with us in Second Life when she left SL.
I put up a vendor in world in the lobby of my apartment building, and another on the campus of Caledon Oxbridge University, so everyone could enjoy this excellent little gadget. And I blogged about it: http://acrossthegridwithlindal.blogspot.com/2016/04/free-hugs.html
A few months later, I became aware that a large number of people were selling versions of Meike's HUD on the Marketplace, for a very wide range of prices. Regardless of price, all of these were no more than Meike's original HUD, which was available for free.
So, I made a Marketplace listing of my own and offered the hugger for free: https://marketplace.secondlife.com/p/Meikes-Hug-Kiss-202/9714182 . Sales have been pretty constant, with about six or eight people a day grabbing a copy.
But one person wasn't satisfied. She left me a one star review, claiming the product was not full permission, as I'd stated, because the animations in it were No Copy. Well, that's quite true. Once you wear the HUD, the animations DO become No Copy. Not only that, the scripts at the heart of the HUD are both No Copy and No Modify. You can't see them to copy or alter the code. This is pretty standard practice for the makers of HUDs and other devices that contain content that's valuable in and of itself.
However, the HUD itself IS full permissions. You can give a copy of it to anyone, and keep a copy in your inventory. The animations transfer right along with the HUD. And the HUD is modifiable; you can take animations out, and you can add your own. You can change the textures and colors of the buttons.
I must admit that I'm miffed. Here is a great product, for FREE, and I went to quite a bit of trouble to create the Marketplace listing and put it out for sale...and I get a one star review and a complaint. Some days you just can't win.