My belief is "reference" implies one has more than one system, and the "reference" is the best one. That may be the most familiar, or most revealing system. If one has only one system then that must be their reference system, regardless of price or sound quality.
Yes, I also do think it is ridiculous- seems like bragging to me. Would a reviewer test a product without putting it in the "reference system"? Obviously not, so why then explain to readers at the onset of the review it was tested in the "reference system" ? Simply list the other components in the system it was used with.