Shopping like this can be disorganised and sluggish (8)
I believe the answer is:
listless
'sluggish' is the definition.
(I've seen this before)
I don't understand how the remainder of the clue works.
Can you help me to learn more?
(Other definitions for listless that I've seen before include "Lacking energy or vitality" , "Lacking zest or vivacity" , "Showing no enthusiasm, torpid" , "Devoid of spirit or energy" , "Lacking enthusiasm or energy" .)