Including "not remote" instead of or in addition to "onsite" will get you downvotes, too. Scrapers and automated search tools are looking for keywords such as those to facilitate searching the list and that breaks those. E.g., consider a posting that says, "We're not looking for Java, Python, or C++ developers" when a positive statement of what you are looking for is far more helpful.
I suppose somebody had bad experience with them. Don't know whether it's the case here, but often the downvoted post indicates that the company does not bother answering to applications or posts advertisment of a position for months but not really looking for anybody or something else is wrong.
