I hadn't heard the term bundleware, but
inherited some early 1890s bundleware that Dad found (yes, found) when I was a kid. Shortly after I
inherited them, I began the unbundling process. There were 11-12,000 cut squares, mostly the common Scott U311. There were many thousands of Scott 219D, 220 (and 220a and 220c), 230 and 231. Many cut squares were large enough to identify business names and/or city to which they were addressed. They were all from Union City, Indiana, located a few miles from where Dad and I both grew up. Many of the stamps were packed tightly into c1900 Clark sewing thread boxes, but all of the cut squares were bundled, 100 each, with either sewing thread or string. The condition of the top and bottom cut squares suggested they had been bundled back when they were collected. My number one regret is that I didn't take any photos before I began the unbundling process.
My recollection is that I was told these had been gathered to sell to a dealer, but I may have have actually been told packet maker instead. I don't know if these were remainders that the individual couldn't sell to anyone or if the individual simply didn't realize that such common stamps and cut squares wouldn't be marketable to a packet maker. In any case, I wrote an article about this hoard that American Philatelist published several years ago. I didn't collect US stamps, but have spent years learning about flyspecking, fancy/geometric cancels and many other aspects of philately that were beyond my areas of interest. It has been a fascinating journey. When I have time, I'll have to share more of this story here on Stamp Community.
Tom