McDonald’s is also maximizing for serving size. Fancy restaurants rarely do this; some pretty much minimize portion size so they can sell you as many overpriced microportions as possible. But a lot of fast food (and chain restaurants) sell huge, cheap portions compared to more expensive restaurants, so it is something of a case of having a whole lot of something compensates for it not being quite what you need.
McDonald’s is also maximizing for serving size. Fancy restaurants rarely do this; some pretty much minimize portion size so they can sell you as many overpriced microportions as possible. But a lot of fast food (and chain restaurants) sell huge, cheap portions compared to more expensive restaurants, so it is something of a case of having a whole lot of something compensates for it not being quite what you need.