Perennial protesters seemingly being rude to barmen (4-1-3)

I believe the answer is:

rent-a-mob

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'perennial protesters' is the definition.
(disparaging term for protestors)

'rude to barmen' is the wordplay.
'rude' is an anagram indicator.
'to'+'barmen'='tobarmen'
'tobarmen' with letters rearranged gives 'RENT-A-MOB'.

'seemingly being' is the link.
This may not be right. Some or all of it may belong to another bit of the clue.

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(Other definitions for rent-a-mob that I've seen before include "Hired crowd (facet.)" , "Crowd for hire" , "mass of people" .)

I've seen this clue in The Times.

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