What really doesn't make sense is that you knew full well what the wait time was but ordered it anyway and now, after doing so, you are complaining about the wait time and canceled your order. THAT doesn't make sense.
On the other hand, Tom doesn't want the headaches associated with running a business with multiple employees, nor does he want to raise his prices due to the increased cost of running such an operation, nor does he want to jeopardize the quality of the Purple Days by having others on the "assembly line". His business plan, while not typical, makes perfect sense. I have no doubt that Tom would prefer to be the Betamax of the vape world, for although Betamax lost out in the widespread home market to VHS, Betamax was STILL used professionally in video production houses, and in the same vein, Tom selling his units just to a small niche of vaporists, I am sure, suits him just fine.
And regarding what would happen to the PD if, God forbid, something should happen to Tom, I personally think it would be quite fitting for the PD to cease being produced if something should happen to it's maker. There's just something very poetic about that, and again, to me would make PERFECT sense.