Yes but.........they could at least make a huge bobbin...that way they could still make money selling their bobbins(if that is the reason they won't go to spools)...
My guess is that they don't see a market for a longarm with an entry level price or a justification to re-tool their manufacturing lines to make a machine with a different style bobbin. I think they would probably have to sell thousands of machines just to break even on the cost of changing molds, etc.