Option to build one from scratch if so desired is certainly a good option and it appears that many have done so. There are numerous go-bys out there, including John's. John even points a couple out in his video of the prototype.
For me it was simply the material cost and function were attractive plus it saved me some time. The materials are sized properly with outstanding appearance, delivered in one box, and ordered with one click.
Plus, as you point out, I like supporting good folks.