They buy things from menu, cross when order is wrong … (9)

I believe the answer is:

consumers

'they buy things' is the definition.
(people who consume or buy products)

'menu cross when order is wrong' is the wordplay.
'when order is wrong' indicates an anagram.
'menu'+'cross'='menucross'
'menucross' is an anagram of 'CONSUMERS'.

'from' acts as a link.

(Another definition for consumers that I've seen is " Those who use or eat something".)

I've seen this clue in The Guardian.

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