I've bought only three games so far but I'm had no problems and I'm not expecting any. This post seems to be more for the sake of starting a flame war or trying to cause a lowering of general opinion regarding this site.
If you have a concern email the GoG support as above. If you wanted to have opinions and a conversation about it then having more that "I wonder.." is probably a good idea. Post why you have concerns and the basis for them.
Also using the "Mark as problem" option when starting a new post is for people having problems and would like solutions. There is no solution to this. Your trust in the security of this site is personal belief. People could tell you that "it's great", "had no problems" and it could have won numerous awards of Internet Safety and you could still doubt the security.
An entirely needless post.
Karl