Commuters are not bread and butter revenue. Relying on the revenue from their fares to pay for the scale of infrastructure and rolling stock required to prevent mutinies by masses of angry commuters is not a way to profitability. Commuters are not willing to pay much higher fares, and with the majority of them using season tickets, do not pay higher fares. Indeed, the normal fare paid on annual season tickets is about the same as off-peak walk-up tickets ant they travel on trains that some times only make one or two return journeys per day. Many staff are required to operate the service for 2-3 hours per morning and evening peaks requiring complicated shift working if wasteful levels in the intervening hours are to be avoided. Unless there is sufficient patronage to fill at least some trains between the peaks, subsidies would have to rise dramatically, even above current Northern levels. In the US and some other car-centric nations, the governments have grudgingly acknowledged that accommodating ever increasing tidal commmuter volumes on public roads cannot be tolerated. They are prepared to commit considerable levels of public funds maintaining financially inefficient peak-only suburban rail systems. So far, the UK has managed to keep a rail system that the general public sees as an asset for off-peak and importantly optional leisure travel. The revenue for that travel helps to defray the massive costs of subsidising commuter's fares.