Ahhh....but I think you are missing the point as well
There are many people who might want to upgrade galley/kitchens because a range has failed, or is on its last leg. Or perhaps because they are doing the whole galley. My neighbor just did hers.
But you see, she has a favorite pasta pot that is huge, has the strainer, etc. She has yet to find a similar pot in iron, or with an iron base. She doesn't want to give up on using this since it helps her to entertain. If someone brings a pot of something for a gathering and its not iron she can still throw it on and heat it up.
Hence, the iron plate.
There also may be some who having spent thousands of $ renovating, might want to hang on to their pots and pans for a while and count those as another large purchase down the road. A nice set can run $400-$600.
Just saying its another option. If it were not a good one why would some induction burners now COME WITH one? As for it being hot, well of course it is! lol I for one have had a hot stove around all my life and somehow survived
I know, I know...that's one of the reasons to GET an induction burner. But there are also reasons maybe to have a plate tucked away somewhere too.