Crossword Genius

Choose, say, to collect money for strike activity (9)

Ross

I believe the answer is:

picketing

'strike activity' is the definition.
(striking workers may set up a picket)

'choose say to collect money' is the wordplay.
'choose' becomes 'pick' (picking is a kind of choosing).
'say' becomes 'eg'.
'to collect' indicates putting letters inside.
'money' becomes 'tin' (I've seen this before).
'eg' placed around 'tin' is 'eting'.
'pick'+'eting'='PICKETING'

'for' acts as a link.

(Another definition for picketing that I've seen is " That may keep strikers in line".)

I've seen this clue in The Telegraph.
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