There is no uniform form for the reference of cases to Magistrates in different jurisdictions. The basic idea—at least in Ohio Courts—is that they free up judicial time for more serious cases; but often the reason a particular case may be referred to a magistrate, may reflect on a particular Judge’s inclinations, rather than a standardized policy, in a Court of general jurisdiction. Each County will likely have a policy, adopted by the Judges of the referring bench.
What I wrote above was referenced to State Courts at the County level, of course. At the Federal level, it would be district by district; but conceptually similar. The general benefit is to free up time in the regular Courts. The show-off aspect in the subject case, of course, makes the whole process something of a joke; but, generally, the benefits would exceed the drawbacks.