Some disreputable types could make certain their reservations book was full for the next four years, then not show up for dinner...
Other disreputable types could give lousy ratings to the place at this site:
http://newyork.citysearch.com/profile/41451747/new_york_ny/freemans.html
And some disreputable types could smuggle in bugs and other vermin.
Or at least freep the reviews online