No, it is not extortion and you can't sue them. You have to bear in mind that no retailer has *any* obligation to buy any particular product or purchase from any wholesaler; it is 100% voluntary who to buy from and what products to carry. A retailer can elect to stop carrying anyone's products at any time, for any reason. And because it is purely voluntary for them to carry your wine, they could put conditions or terms on carrying it, such as requiring you to pay to advertise, or giving them a better/lower price, or agreeing to buy back unsold inventory, etc. If you refuse to do what they want, they can buy from others, just like if you don't like their terms, you can refuse to sell to them but can sell to their competitors. The wholesaler-retailer relationship is voluntary and you cannot force them to keep buying from you (like they could not force you to sell to them). Therefore, there is no legal claim.