>>10471889The foam ones were also sold locally in discount stores, they had butterfly sets too (see picrel). These were more appealing because of their bright colors. They still make them too, but now stickers rather than paint so they are a little more durable now.
Where in the world are you, anon? They sold a lot of balsa gliders in shops in the U.S (A.C Moore, Michael's, Jo-Ann, Hobby Lobby, Toys R US, etc.), as well as in specialty hobby stores. Usually older (silent generation) parents and grandparents bought them for their children or grandchildren.