It is really not about the money. I have a big pile of rough-cut butternut sitting in my garage that I want to see how it machines before tackling a bigger project with it. My wife is out of wood chips for the rabbit and is threatening to buy some if I don't plane some wood soon. My son has been asking to work with me on some woodworking projects. These darn blocks will cost me $20 each in time and effort but my wife will have her chips, my son will get to make some things with his dad, and I will smile every time I pick one up for decades (long after the butternut tree has gone the way of the American chestnuts due to the cankers that is killing them all).
Plus they "cost" me nothing.
Really is similar to reloading. I don't really think it will be cheaper than buying .223 at $.28 each or 9mm at $.18 each for brass cased. I will be shooting my own stuff. Plus when the UN decides that we need to serialize and register every bullet and case (for the children), I will just keep working through my stockpile of components.