Check the article and determine if they are specifically talking about using a kit.
Most likely, they are not.
Making wine the traditional, non-kit, way doesn't use a carboy for a primary. When using crushed fruit, instead of concentrated juice, one needs a large mouthed, open top primary, such as a bucket, tub, vat, crock, churn, etc.
This type of primary fermentation requires oxygen, and the cloth covering is to allow air/oxygen access to the must while filtering insects, dust, debris out until it's ready to rack into a secondary fermenter, usually a carboy.
Also, during the primary fermentation, the winemaker needs daily access to the pulp in order to push it down to the bottom of the primary, which enhances the fermentation process.