Just got an email about it, not looked into it yet :
http://www.groupbuyseotools.net/
Being an ambassador for Majestic in Scandinavia, I see these all the time and report them all. Majestic is great at hunting these down and banning accounts left and right.
IMO it's basically stealing and I loathe it.
The worser or lesser version of this is when someone else steals your stuff & offers it as a free throw in with some other stuff they are selling. Then you start getting waves of "customer" support requests from what amounts to non-customers. I think I flamed the crap out of a guy for this about a decade ago.