They jeer at consumers (8)
I believe the answer is:
scoffers
'consumers' is the definition.
(scoffer is a kind of consumer)
'they jeer' is the wordplay.
I cannot quite see how this works, but
'jeer' could be 'scoff' (synonyms) and 'scoff' is found within the answer.
The remaining letters 'ers' is a valid word which might be clued in a way I don't understand.
This explanation may well be incorrect...
'at' is the link.
Can you help me to learn more?
(Another definition for scoffers that I've seen is " Mockers and devourers".)