My husband and I purchased a bottle of gamay rouge...

My husband and I purchased a bottle of gamay rouge along with lots of food to have a picnic at the winery. The wine turned out to be VERY sweet. There was no indication on the bottle of the high sugar content. When we tried to exchange the wine, we were refused. I have never in my life had an establishment refuse to take back undesirable wine.
This will be our last visit. The management has no idea how much revenue will be lost from their poor judgment.