One thing I haven't seen mentioned here is, crowd response to open carry. If you open carry and something bad DOES go down...you are now the person everyone is going to hide behind, and they will all expect you to save them. Because they've all seen your gun, amd now its your "job" to keep them safe.
Maryland - believe it or not - does not distinguish between open or concealed carry once you have your permit. For me though...always concealed. I don't want the attention.
I'm not a cop. I'm not here to protect you. I have no illusions about that. I carry to protect ME, and the people important to me. Yes, that generally includes a crowd of innocents if the situation presents...but the situation may well call for an exit, not a stand. And that would likely **** off people left behind, if they knew I had a gun...and used it to fight my way to safety, instead of trying to defend the entire stadium.