Puts up a fight defending an alternative opinion dividing the customers and publicans (8)
I believe the answer is:
counters
'puts' is the definition.
The answer and definition can be both acts as well as being plural nouns.
Perhaps there's a link between them I don't understand?
I can't explain the rest of the clue.
Can you help me to learn more?
(Other definitions for counters that I've seen before include "Argues in reply, parries" , "chips" , "Opposes the surfaces in shops?" , "Horizontal surfaces on which business is transacted" , "Returns" .)