My wife and I both have CPAP machines so we do use a fair amount of distilled water. With empty shelves more prevalent lately, I have seen sporadic shortages but I have always been able to find it when needed. We usually keep 4-5 gallons on hand at any one time. I know that some people will also use it for making coffee, but my reverse osmosis system takes care of our needs on that front.
Given that it is generally less than $1 a gallon and I am still able to find it locally, I guess I would be hesitant to drop the cash on a machine for my home. If I do the math, I'm thinking the machine would probably pay for itself over the course of 3-4 years but the low cost and convenience of simply buying it at Walmart overrules that. Plus, it would also mean that I would need to find the space on my kitchen counter for yet another appliance so in the end I think I would pass.