I don't see that negotiating is anything other than normal business practice. Organisations may set a flat fee but you are entitled to ask if there is any leeway. Bands negotiate all the time. It is not as though they are selling 15 identical pitches all with an identical amount of passing trade, similar proximity to entrances etc.
If a man who thinks of himself as having some significant social standing in the folk world retains a grudge against a woman after a year, then this tells you far more about him than it does about who was marginally in the right or wrong last year - even assuming there was a right or wrong side to it all.