60% of sales is “direct to consumers” (DtC) for an average American winery, according to a recent report by the Silicon Valley Bank. Rob McMillan of the Premium Wine Division of the bank says that direct sales have grown dramatically over the last five years. This is an astonishingly high number. In Europe, only wineries in areas with a very high number of tourists, like Provence, have similar numbers (according to my anecdotal experience).
Direct to consumer sales give the wineries various advantages, e.g. better margins (no middlemen) as well as a direct contact with the consumers. Read more on this report from SVB on wine.