During the history of sewing, the chain stitch has held its own place within the development.  Chain stitch sewing machines were manufactured for home use and for use as "first" machines for young children.  They also were used in the apparel industry.  For example, the hem on jeans is done with a chain stitch machine.  The first chain stitch machines were used in France by a tailor named Thimmonier, as shown in the documentary The History of Sewing Machines . Mr. Thimmonier used the machine he had invented to have a business sewing military uniforms.

Below is a toy model chain stitch sewing machine, the Gateway Engineering Junior Model NP-1.  Marketed to children, the simple chain stitch it creates is also able to sew seams for items other than for children.  I have posted two videos showing some minor adjustments I had made, as well as sewing with this small sewing machine.

1950s Gateway Child's Sewing Machine