I'm not sure you deserved to be down-voted because it's a legitimate question.
Fortunately I don't think that anyone has tried to claim that posting to HN makes you a hacker. It's (news (of interest for hackers)) rather than (news of interest (for hackers)). So posting doesn't mean you are claiming to be a hacker, just that you are interested in the stuff hackers are interested in.
By the way in my view some of the most interesting hacks are done in Excel (for example the guy who wrote an Excel 3D engine - http://www.gamasutra.com/view/feature/3563/microsoft_excel_r... - no one can seriously claim that this isn't a hack in the best sense of the word.) Making constrained systems do things they were never designed to do is practically the definition of hacking.
Maybe, if you assume this is a clubhouse only for hackers. I think the purpose is more like "news that would be of interest to hackers", which implies others could have interest in the same topics. If a recruiter posted in this thread it certainly wouldn't be out of place.
Even people who wrote an single excel script call themselves hackers here (and are defended for it! I've seen it happen)
EDIT: At this point in my life I'd be embarrassed to be called a hacker. So I don't feel ashamed being an impostor here.