The "high end vodka" thing is such a joke. A few years ago, one of the vodka companies put an article into Wikipedia with all their high-end vodka hype. That did not end well for them. People started digging for reliable sources about the company, and found them. Turned out the vodka company was entirely a marketing operation. Production, bottling, and distribution was outsourced to another company, one that makes liquor products to order in addition to marketing brands of their own. That company is quite open about what they do in the trade press, so lots of reliable info was available.
The ethanol came from an industrial refinery sized plant in the Midwest, where corn went in and ethanol and cattle feed came out. Some of the alcohol was re-distilled for beverages and cosmetics, and some of it went to oil refineries to be blended into gasoline. Tank cars of ethanol went by rail to the outsourcing company, which had its own railroad sidings. The outsourcing company took in ethanol, did a bit of re-distilling and polishing, added de-ionized tap water and flavoring, and bottled. Just like they did for the other thousand or so products they make. No secret in the industry, but something the general public usually doesn't find out about.
It's all bottles and labeling. The outsourcing company admits they make a thousand different brands of booze, but only have a hundred different recipes. The company moved to an area north of San Francisco a few years ago to be next door to the bottle-making plant, and have better rail access. All that ended up in Wikipedia.
There's an interesting economy of scale in doing it this way. Under US law, the booze industry is divided into distillers/brewers, wholesalers, and retailers. Usually, the distiller/brewer makes the final product and bottles it, there are bulk shipments of bottled goods to wholesalers, and wholesalers are basically a fulfillment operation serving retailers. But the way this outsourcing company does it, the distiller/brewer is an industrial plant sending them tank cars of ethanol, and they make up the consumer product and distribute it to retailers. Only one step of trucking instead of two.