Compagnons in other professions don't have the luxury of having everyday objects that work well as a show of skill. Plumbers masterworks, for example, usually look like an intricate mess of pipes with no purpose. It doesn't speak much unless you know the trade.

Another thing to realize is that compagnons are not any workers, they are masters. Maybe few people want grand wooden stairs today, but some people do, and compagnons are the ones who are getting the job.