Crossword Genius

Drinkers seizing last of beer obtained capacious bags (5,8)

Ross

I believe the answer is:

cargo trousers

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'drinkers seizing last of beer obtained' is the definition.
I know nothing about this answer so I cannot tell whether this works.

'capacious bags' is the wordplay.
'capacious' becomes 'cargo' (I can't explain this - if you can you should believe this answer much more).
'bags' becomes 'trousers' (I've seen this before).
'cargo'+'trousers'='CARGO TROUSERS'

Can you help me to learn more?

I've seen this clue in The Times.
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