Never underestimate the power of small, but highly motivated groups of people. This store's new manager likely got the job through back channels as opposed to actually being qualified, and quickly proceeded to run the place into a state of complete disarray. Morale was low and several people even left, but one guy was determined enough to take action and organize his fellow employees to take a stand.
In the end, they had more than enough evidence
to take her down, AND made corporate take them a little more seriously in the future.