Crossword Genius

Marshal notices seats occupied by 1,000 holders of these? (6,7)

Ross

I believe the answer is:

season tickets

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'holders of these?' is the definition.
I don't know anything about this answer so I cannot tell whether it can be defined by this definition.

'marshal notices seats occupied by 1000' is the wordplay.
'marshal' indicates anagramming the letters (I've seen 'marshals' mean this (marshal can mean to gather)).
'occupied by' is an insertion indicator.
'1000' becomes 'k' (synonyms).
'notices'+'seats'='noticesseats'
'noticesseats' is an anagram of 'seasonticets'.
'seasonticets' placed around 'k' is 'SEASON-TICKETS'.

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I've seen this clue in The Guardian.
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