Bigger is not better. At least in wine production it's not and that's one reason why you don't see as many familiar labels here as you do in other stores. A lot of experience tasting and selling wine has shown us that smaller production is most often better. You could call this a "farmstand mentality". It's the idea that a homegrown tomato is better than one from the supermarket. Especially if the person farming the produce has a connection to his land and does the work in the field to ensure health and ripeness. Better product, better flavor, fresher, more identity and personality. Grapes, like any fruit or vegetable, have variations in quality and ripeness when they are grown. Attention to these details is not what you'll find with enormous wineries. Winemakers need to do some sorting to get rid of the inferior bunches. This is more work but also more readily accomplished when the grapes are picked by hand from vines behind the house. Will you pay more for these products? Yes, but not always that much more, the wines in this photo all sell for between $10 and $15 a bottle.
You could pay less for a large scale bottling but you'd be making compromises to save a few dollars. You would be supporting industrial farming and all of it's cost cutting measures like aerial spraying of pesticides and fungicides. You would be supporting purchasing grapes from multiple growers whose incentive is to sell the most grapes they can to the winery rather than the best quality grapes. And those sources are going to change from year to year so that you don't really know what's in the bottle. What you wouldn't be supporting are small farmers and winemakers who make a carefully tended product as naturally as possible, who have pride in their work and place their family name on the label. Is that worth a few extra dollars? You bet.