My experience with playing more traditional genres of music is primarily in sessions at pubs or in the homes of musical mates. I really never played for contra or ceilidh and the such though I thoroughly enjoy them and the music.
When my swing group, DC Ambiance, performs at a festival, restaurant or pub it's not unusual to have a couple here and there get up and swing dance to our music. But performing or jamming is very different than actually playing for a swing dance.
Styles of dance (Lindy hop, jitterbug, west or east coast swing, Balboa etc.) require specific styles of music and tempos. For the dancers there are some set dance moves and styles but their choreography is just as creative and individual as the musician playing a solo.
Our group has recently been booked to play more of these dances. It is a fun challenge to come up with ever increasing ways to to keep pace with the dancers.
Just saying...