Seriously?

[PepperElf]

and there's always the tactics of word-of-mouth.
if enough people find out about how sucky they were towards their customers.... they often start doing better.

and... if not the manager... if it's a local store you can always talk to the owner. One of my friends did that... they had bad service & the manager was really rude, not realizing that they were friends of the owner. Needless to say the manager wasn't there a week later.