$2000? That's it? Not surprising that "Less than 2% of all prospective employees end up accepting the offer."
Having a flat customer service organization (and valuing making customers happy) sounds like a great way to filter for reps who can think independently and find ways to make customers happy (and themselves more efficient).
I'm actually surprised they don't see more people gaming the system, applying to get the bonus without any intention of working at Zappos.