The fast-paced lifestyles experienced by many players in the entertainment industry often leaves them little time to discuss new projects or meet with old friends. Consequently, the expression "Let's do lunch" has become Hollywood shorthand for planning any sort of meeting during a lunch hour. Whether or not the actual lunch date comes to fruition is a secondary point, as long as the agreement to meet has been made. The details necessary to turn a flippant offer into an actual meeting over a meal are often worked out later by others.
Whenever a powerful public figure issues the familiar "Let's do lunch" decree, it often sets off a chain of logistical problems to be handled by personal assistants, private secretaries, publicists, or agents. Since many celebrities' lives are scripted to the minute, it is not easy to pencil in a lunch date with an old friend or a potential client. This is the job of their "people," a subgroup of assistants whose work duties include selecting an appropriate restaurant, notifying the invited guest of time and place, and handling any potential disruptions during the meal. For some of the most powerful public figures and executives, the lunch offer sometimes turns into an event of military-like efficiency.
Unfortunately, sometimes the invitation is not meant to taken at face value. Because a celebrity or executive may have an extremely busy schedule, any request for a face-to-face meeting could become impossible. The expression is considered by many to be a polite brush-off, since the chances of actually meeting with that person again are clearly minimal. Unless the invitee actually has "people" who can coordinate a real lunch meeting, it's much more likely that a lunch date of any kind will not take place.
One aspect of the invitation is the opportunity to impress other powerful figures who may also be in the room. This is known in entertainment circles as schmoozing and is generally accepted as a way for a person to introduce himself to potential backers or co-stars. Because many important deals have been known to happen during these lunch dates, the invitation to "do lunch" is sometimes viewed more as an opportunity to network with powerful people than an actual meal between friends or co-workers.