It appears that for a while, wineries could not advertise over the internet or engage in e-commerce, even though liquor stores can do so. Minnesota wineries could only rely on word of mouth and/or other forms of advertising to let people know of the existence of Minnesota wine. This is a bad predicament to be in since consumers are now getting used to and liking the act of buying over the internet. Litigation in Minnesota has led to victory for vintners and consumers to freely conduct their business in due course.
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Also contains some good background on the Minnesota Wine Industry and other related information.