Cosmo Kramer: It's a write-off for them.
  Jerry:        How is it a write-off?
  Cosmo Kramer: They just write it off.
  Jerry:        Write it off what?
  Cosmo Kramer: Jerry, all these big companies, they write off everything.
  Jerry:        You don't even know what a write-off is. 
  Cosmo Kramer: Do you?
  Jerry:        No, I don't.
  Cosmo Kramer: But they do, and they're the ones writing it off.

Edit to be fair: the "500 minus tax write off" comment does make sense but often people overstates the benefits of writing things off.