Delights when ecstasy and amphetamines mainly overrun America’s charities (6)
I believe the answer is:
treats
'delights' is the definition.
I can't explain the rest of the clue.
(Other definitions for treats that I've seen before include "At rest (anag)" , "Entertains with taters" , "Stands a round, say." , "Behaves towards or deals with in a certain way" , "Entertains at one's own expense" .)