There is a winery in virtually ever village. There is wine everywhere. It mystifies me that there's so little Portuguese wine available in the US. My faves are from the Alentejo region.
I think Portuguese wine is better than Napa wine. And a really nice bottle of wine here is almost always less than 10 euros in the shop (as opposed to in a restaurant). know a lot of people who make their own wine. I mean, it's very, very common.