Well, no two munches are the same. Some are held in bars or pubs, some in restaurants and some in coffee shops. Most are held in public spaces although some munches are hosted in a private room or separate part of the bar or restaurant. However, the ethos of nearly all munches is to provide a safe, social setting for like-minded kinksters to hang out and chat. Whichever venue the munch is held in will to some extent dictate what the event is like, but as a general rule you can expect a large variety of people representing all sorts of kinks and relationship dynamics - and conversations that span the everyday topics of life in general with a smattering of kink thrown in.
Some things to keep in mind, though. First, people often like to remain semi-anonymous and so asking someone what they do for a living, exactly where they, live or even their real name is, in general, not going to endear you to anyone. People will often use their scene name or just their first name. Be content with whatever level of information someone feels comfortable sharing with you at this point. You should also think about what you want people to know about you before going along.
Because most munches are held in public venues, you should wear whatever you would normally feel comfortable wearing to a bar or restaurant. Some discreet fetish wear is usually fine but nothing that is going to frighten the locals or even draw an excessive amount of attention to the group. Most munches try to operate with a certain amount of discretion to afford some privacy to both the people who attend the munch and also to ensure that the venue is happy to have them.
