It’s a continuous struggle in the running of restaurants, balancing the desire of guests to dine at 8:00pm, while maintaining standards of service.
You may see a virtually empty dining room when you walk into a given restaurant at 8:00pm some Thursday night. The host may advise that there will be a wait, but if you’d like to grab a drink at the bar, a table should come available in 20-30 minutes.
“But there are all those empty tables!” you protest to your date as you order your g&t.
Those tables may be reserved for reservations that are coming in within the next 30 minutes. Or there may be a large party in an unseen private room that is slamming the kitchen at the moment.
It’s not merely an equation of
x (# of chairs) – y (# of reservations) = N (# of tables available)
The math involves everything from the number of staff you can fit behind the ‘Line’ in the kitchen, how many dishes on the menu come from the same station (the grill, the sauté, the pantry), how many bodies you have on hand to literally bring the food out from the kitchen, clear and reset the tables, make the drinks, and greet those guests. Booking more guests than you can logistically handle in one fifteen minute window will slam your kitchen and your waitstaff, slowing service for everyone that comes in after you. So it’s more like:
In the running of a restaurant, great service is the culmination of hundreds of small moments and tiny details. Ideally, their server greets every table within 2 minutes of being seated. Waters hit the table within five minutes, followed by the first round of drinks moments thereafter, the order is taken within 8 minutes, and the appetizers are well on their way out of the kitchen by the fifteen-minute mark.
In that world, spacing tables out even ten to fifteen minutes helps immeasurably to keep service running smoothly. At 8:15, the orders are all in for the servers’ tables that sat down at 8:00, and now you will have her full attention. Who wouldn’t rather have that, than silently fume that you haven’t even gotten bread yet, while the couple at the next table is cooing over their glasses of Petite Syrah?
There are many, many reasons that a restaurant will tell you that they can’t seat you at a certain time. They all, ultimately, boil down to a desire to give you the best service possible when you dine there.