A pub doesn't have the same floor dynamics as a restaurant. Tables change occupants several times a night, groups merge or split, payment often comes at the end of the night instead of course by course. A system built for the slow rhythm of a structured meal doesn't cope well with this kind of fluidity.
GrazieChef handles merging and splitting sessions right from the interface: if two groups push tables together, their orders can stay separate or merge into a single bill; if one big group wants to split the bill at the end of the night, splitting takes a few taps instead of a calculator while the queue at the till grows.
Happy hour is probably the trickiest feature for a pub: different prices in a specific time window, often only on some categories. Set up once, it applies itself — nobody has to remember it during the rush, and no customer complains about a wrong price applied outside the window or forgotten.