You sure know how to make a guy feel old ...
I grew up in the Owatonna, Mn area, about 25 miles from Waseca, Mn where Heters had their "showroom". I drove a Heters snowmobile as a kid and my Dad would take me over there to buy treble hooks and lead weights (for dough balling Carp) while he shopped for lures for the annual fall fishing trip to Lake Winniebegosh and Cass Lake with the boys. If memory serves me correctly they even had a catalog. Someone bought them out and they fell to the wayside after that.
I have been in a Gander Mtn in Rochester, Mn and in a Twin Cities south suburb within the last couple years so I believe that they're still around.
I don't know if that was Heters only showroom, but it was the big treat for like a 10 or 11yr old to go to with Dad.
I did a quick search for Gander and they're still around. Kind of entertaining, along with driving instructions they give GPS coordinates to the locations. I knew I bought that GPS for something.