Around here open bar is the norm. If you have a cash bar or no bar at all you will be talked about and by a lot of the people. If people know in advance they may even bring their own alcohol instead of going to the cash bar. I've heard a lot of stories around here about just that and trips out to the car or flasks in purses.
I have been to two dry weddings, one because the bride's mom was a recovering alcoholic and the other because of the religion, but never to a wedding with a cash bar. I know it is regional just like cash vs gifts, cover you plate, and so on but just like those things if you go against the norm in your area it will stand out and probably be talked about.
All that being said it is a day for the bride and groom so if there is a compelling reason not to have an open bar don't get pressured into it, just accept the possible reactions.
LOL, I'm not a wine drinker but a couple years ago I went to a wedding at a winery.
Of course they only served wine. I went up to the bartender and asked, "I'm not a big wine lover but do you have anything white that's not too dry?"
His reply: "How about a glass of water?"
I laughed my butt off.