another option is to buy shuffleboard wax (ebay or large janitorial supplies) aka
ballroom wax. This is a fine powdered wax that comes in various "slipperiness"
grades...a tiny bit of a moderate slipperiness goes a very very long way. A container the
size of a kitchen cleanser 'can' could last an entire dance community a year.
Since it is a wax, I imagine it is good for wood floors, however the venue must be
consulted and there is some danger from exuberant use such that folks could end up
horizontal. Sprinkling it evenly around the floor and then sweeping it off before the
dance will generally leave a beneficial amount.
Alternate solutions might be to offer a 'step in' tray of it, where those who
found the floor too sticky might smoosh their shoes in it briefly or a bottle could be
passed around so dancers could put a pinch in their palms and rub it on the bottom of
their dance shoes from time to time. I suspect this works best on smooth soles (suede,
leather, composite) and not so well on 'tread' soles like athletic shoes. I carry
a small plastic bottle of this to all dance events to rub on my own shoe soles.