Everything lives on one page on purpose. Someone deciding where to eat is not going to work through a navigation tree — they want the food, the hours, and a table, in that order, with a thumb. So the page is a single scroll: hero, specials, menu, reviews, hours, book. There are no sub-pages to lose anyone in.
The reserve button rides along the whole way down rather than sitting once in the header. Photography leads, because people choose a restaurant with their eyes — but the menu prices are real text, not a photographed board or a PDF, which is what makes them readable on a phone and findable in search. Reviews sit directly above the booking call-to-action, where the last of the hesitation happens.