Yeah, you are right. If at least the comment will be different it will not look like spam. But if the same comment just copy past everywhere, it's not nice at all. I forget also to tell about those upvote their spamy comment to make it in the top. I don't like that also. If they want to promote their project, they should let it go to the top naturally, not upvoting it and hide other comments. Some of them even upvote the comment and don't upvote even the commented post.