Agreeable remark reduced rent in food store (10)
I believe the answer is:
pleasantry
'agreeable remark' is the definition.
(I've seen this before)
'reduced rent in food store' is the wordplay.
'reduced' means to remove the last letter.
'rent' becomes 'lease' (I've seen this before).
'in' indicates putting letters inside.
'food store' becomes 'pantry' (cupboard for storing food).
'lease' with its last letter taken off is 'leas'.
'leas' placed inside 'pantry' is 'PLEASANTRY'.
(Other definitions for pleasantry that I've seen before include "Slightly amusing remark" , "Humorous style" , "jocularity" , "Jocular comment" , "Sally" .)