Here’s an article I found in The Screw, an underground newspaper from Kansas City, MO (Aug. 1, 1969):
Dennis’ Free Store
Are you tired of the shirt you’re wearing? Go down to the Free Store at 39th & Main across from The Beacon, take it off, toss it down, look around, find another one, put it on and leave. The Free Store has plenty of shirts, pants, shoes, boots, records, books, and jackets. You can have any of them you want. Just bring in something, anything, and take out whatever you like. The proprietor of this store, Dennis Giangreco, doesn’t want to make any money, he just wants you to come down and take his stuff away. There has never been anything like a free store in Kansas City. It goes beyond any of the “hip” shops we have had because everything is free and it exists completely outside the capitalistic framework of profit motives. Also it is not a Mission Hills owned philanthropic “thrift shop” designed to put second hand goods within the reach of the impoverished; those poor devils god help them, we simply must do something for them this very afternoon when we’re through shopping at the Plaza. The Free Store has political implications that no hip shops have had before in Kansas City. Its very existence tends to undermine the dream of making a fast buck. It represents the sentiments of a community that feels leisure to be more important than affluence and “getting ahead”. The shop could use some book cases and clothes. Go down to the Free Store, give away your stuff and get some different stuff.
digger feed: dinosaurs are dancing 
The guy who did the Motherlove Free Store is the same “Trucker Dennis” mentioned in this article – http://kcrockhistory.com/2019/03/where-did-the-name-volker-park-come-from/. He later became a historian and author. The Westport Free Health Clinic he helped get off the ground and organized benefit concerts for is still in existence – https://kccare.org/about/history/ – though it went through some big changes about 20 years ago.
And this has to be him too – https://www.thecrimson.com/article/1977/4/23/new-parody-is-ridiculing-the-phoenix/.
I was a 15 year old, throwing papers for The Westport Reporter about a half block away. And I remember the Free Store. The items in the store were laid out in no particular order. And the staff, similarly displayed.