I have been getting invites like this from random people for the past month or 2 months and messaging me saying weird stuff like this. I always remove the person if he, she sends me messages like that or I decline invitations.
The reason why I accept people is because some of them have names when they send me invitations that I think are some people I play with in EVE Online, World of Warcraft or some other video game that I played with, but if it turns out it's not that person then they get removed.
Also yeah I agree this topic should not turn into a Digital Rights Management (DRM) discussion because people can steal from you from gog.com as well, accounts on any web sites can get hacked if you are not careful.