Photo taken: filled up outside? (9)

I believe the answer is:

picnicked

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'filled up outside?' is the definition.
The answer and definition can be both related to consumption as well as being past participle verbs.
Maybe they are linked in a way I don't understand?

'photo taken' is the wordplay.
'photo' becomes 'pic' (short for picture).
'taken' becomes 'nicked' (UK slang for stolen).
'pic'+'nicked'='PICNICKED'

Can you help me to learn more?

(Another definition for picnicked that I've seen is " Dined out".)

I've seen this clue in The Guardian.

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