@eta The phrasing also seems to be that it's only "consumption" that's forbidden, so I guess if someone opened a bottle of cider a bit earlier, they are now expected to sit with the opened cider bottle until the train passes the stretch without drinking it, and the security people are expected to pay attention to whether the cider is actually being drunk?
From similar weird partial-route prohibitions, S10 in Zürich (a commuter-type train, ~10km long route) has a 3-station-long interval where bikes cannot be carried on the train. (The reason there was to reduce the amount of downhill bike riders in the area.)