They sell booze and repackaged TV dinners (unopened) (8)
I believe the answer is:
'they sell booze' is the definition.
The definition suggests an adverb but the answer is not.
'repackaged tv dinners unopened' is the wordplay.
'repackaged' indicates anagramming the letters (I've seen this in other clues).
'unopened' means to remove the first letter.
'dinners' with its initial letter taken off is 'inners'.
'tvinners' with letters rearranged gives 'VINTNERS'.
'and' is the link.
Can you help me to learn more?
(Other definitions for vintners that I've seen before include "Wine merchants", "trades in port, perhaps", "14 [SWANUPPING] company".)