Leaving tips hurts feelings (7)
I believe the answer is:
offends
'hurts feelings' is the definition.
(I've seen this before)
'leaving tips' is the wordplay.
'leaving' becomes 'off' (as in 'I'm off').
'tips' becomes 'ends' (I've seen this in another clue).
'off'+'ends'='OFFENDS'
(Other definitions for offends that I've seen before include "annoys" , "Causes resentment" , "Hurts the feelings" , "Breaks the law" , "Insults or causes displeasure to" .)