Other than fast food places, pretty much everything in Northern Wisconsin has a Class B LL.
I've OCed into all kinds of supper clubs with absolutely no issues. I don't drink, but do go to a bar occasionally with friends. I've heard the OC only in bars with the owner/manager permission a lot, but I can't find that anywhere in writing. I think it is like any over establishment, they can ask you to leave for whatever reason, it's their business.
I've asked about OC at a couple of bars and have always been told no. I've never just walked into a bar OC to see what would happen, I expect you would get mixed results. If I know I will be waiting in the bar for a table in the supper club, I will wear a sport coat, or a light jacket while in the bar, then take it off for dinner if I get warm.
Tomahawk Fall ride this weekend, I'd bet there are more than a few firearms in bars around here. I don't know about how many OC tho. I've also heard you can walk through the bar to get to the seating area if needed or to the bathroom, OC. But again, where is it in writing?
I also CC in church as another poster mentioned. Personally, I wouldn't have an issue with OC , but I guess I respect that there might be some others that would. I have mixed feelings about it and have asked the Elders what the policy is on it. They asked me if I thought it might happen and I said yes. Meaning but not saying, me. Given today's crazy world and hostilities toward religious groups, I feel a church is probably one of the most needed places for some protection. Given the amount of untucked shirts, vests, and sport coats in the summer, I'd say I'm not the only one thinking that. Thank the Good Lord for air conditioning!
Bottom line answer to your question best I can figure. Yes, you can open carry in a bar as long as you have a license that is recognized by Wisconsin, and you are not drinking. But, I would expect to be asked to leave or conceal. I suppose technically, you could refuse to conceal, but you would have to leave or be subject to trespassing charges. So, it might be a two step process? The only thing I know for sure is that it is all seems way too complicated and unclear.