We don't have Renaissance Fairs in the UK, but they have been discussed at some length on here and it seems fairly clear that they are not folk festivals, although they may include some folk music. As Don pointed out, the whole point of these events is the dressing up, so it is a bit strange to criticise people at them for doing so.

The majority of people at folk festivals don't dress up in costume. Admittedly, at some festivals in the UK a few people can be seen wearing distressing trousers, and in the case of some women, fairy wings (!), but these aberrations are confined to a small minority and are easily ignored.

I've visited folk clubs and sessions in most parts of the UK. It's true that my experience of the North East is limited, but elsewhere I've seen little evidence of heavy drinking. Steady drinking, yes, but there's a difference between sinking 9 pints in the space of a few hours and drinking the same amount over the course of a whole day, which is the more usual pattern at a festival. At a folk club, most people manage with 2 or 3 pints - less if they're driving.

Conrad, you appear in your travels to have the unfortunate habit of ending up in places with extremes of behaviour - heavy drinkers in Newcastle and compulsive fancy-dressers in Baltimore (although no one else seems to have seen them).

However, you're missing the point. If you were truly interested in the music but concerned about the cost, you could easily cut back on your intake of beer to make the evening affordable. Your priority is clearly drinking beer rather than listening to music. To claim that this is an essential part of the tradition is laughable. You don't have to be fighting drunk for people to find such behaviour objectionable.