Our Indian tandoori chef was also very unfamiliar with hing. When I showed him a tub I had, he asked me what I would use it for. He had never seen it used in any of the restaurants he had worked.
As for Sam being self taught, I think it's because of a "passion" for it. Some trained chefs are just "doing a job.e" Entrepreneurs always do much better IMHO.
Seems some people just want to nit pick at anything.