I ran across https://hardwarerecs.stackexchange.com/q/24/1 today, with Robert Cartaino leaving this comment:
"Hardware Recommendations" was created for questions seeking a specific hardware products given a set of definitive requirements. If your question involved general computing or hardware issues, it can likely be asked on Super User; but nevertheless, it is outside the scope of this site. – Robert Cartaino ♦ 9 hours ago
I would agree with this, on largely the same basis as Robert's answer here, but I figure we should discuss it as a community.
So: Are questions that ask why one would by a thing on topic?