I know of one or two in Missouri that certainly seem to. At least based on some of the wine types that the sell (Peach Apricot Chardonnay, acai Raspberry something)
Some must run kits, but I don't know that it would be usual grape types. Of course we often have no idea what wineries do for chaptalizing, etc. I have seen the super-size kits that cmason1957 is talking about. Labelpeelers carries 'Winery Series' of the Island Mist flavors, 4x the size of the home version with pretty box.
Not related to smaller wineries but Tim Vandergrift suggests that many of the biggest wineries in U.S. by volume will use concentrated grape juice so that they can make 2 or more batches a year, rather than just once a year: Wine Skins in Recipe Kits
Quoting from the linked story (which has been posted on WMT before): If you look at a really big company like Gallo, Mondavi, or Bronco Wines (they make Two-Buck Chuck) they all turn out wines in a price segment that needs fast turnover. They make wines on a very fast schedule, and can often turn a tank over twice, or even more often, per year.
But they only get one harvest, and it's a gigantic one. If they kept all the grapes and juice at full strength they'd need twice as many tanks as they currently have. By concentrating part of their harvest and making part of it into sterile, single-strength juice they can store it until they've sold the first part of the harvest, and then make more. It's important to note that alcohol producers pay tax on the wine when it's made, not when it's sold. As long as it stays juice, it's untaxed.
If you read between the lines, an awful lot of commercial wine is made exactly like wine kits, with the same raw materials, and the same techniques. That's why I find it consistently funny when anyone says they don't like 'kit' wine—they're usually already drinking it, but paying way more from a commercial source!
If wineries didn't try to change to some degree there'd be nothing different to try ,just the same old same old.
It's hard for wineries to think outside the box.
At least that's my take.
Big wineries making mainstream wines? Yes, I agree. But looking at the wine lists of small wineries in NC, I see a lot of inventiveness geared to capture market share and make sales.