The real money move for restaurants is actually in the data they collect from pre-orders. When someone books a table or places an order online, the restaurant learns what they want, when they want it, and can start building a customer profile. That information is worth more than you'd think - it helps them figure out what to stock, when to prep, and which menu items to push. A place that knows they're getting 40 covers at 6:30pm on a Friday with twelve people ordering the salmon can literally cut their waste in half compared to a restaurant guessing and prepping for chaos.
But there's also a psychological angle people gloss over. Walk-in traffic is genuinely unpredictable in ways that mess with both staffing and morale. You either pay people to stand around during slow periods, or you disappoint customers who show up and get told there's a two-hour wait. Pre-orders flip that - staff gets scheduled with confidence, customers know exactly when their table or food is ready, and there's way less friction on both sides. Some restaurants discovered they could actually run leaner teams this way because nobody's burning out from the dinner-rush roulette.
The food waste thing mentioned earlier is real too, but it cuts both ways. Yes, you can predict inventory better with pre-orders, but you also lose the spontaneous crowd. Places that figured out how to hybrid this - still taking walk-ins but limiting them - tend to do better than going all-in on reservations only. The ones doing online-only orders are usually smaller spots that realized their margins were too thin to gamble on foot traffic anyway.