I had the same observation in the US (and Canada) but it to me it seemed like they were over-staffed rather than the UK understaffed!
With public transport in the US often very underfunded, I suspect that the difficulty of reducing staff counts means that other things, such as NYC's crumbling and often dystopian subway stations go unaddressed.
Amtrak seems to need 3+ staff to manage a 4 or 5 car train (in addition to catering staff and drivers) and VIA often has one staff member per carriage. There's a balance though. On Chiltern recently someone was taken ill and with no guard it was hard to get help and communicate with the driver.
With public transport in the US often very underfunded, I suspect that the difficulty of reducing staff counts means that other things, such as NYC's crumbling and often dystopian subway stations go unaddressed.
Amtrak seems to need 3+ staff to manage a 4 or 5 car train (in addition to catering staff and drivers) and VIA often has one staff member per carriage. There's a balance though. On Chiltern recently someone was taken ill and with no guard it was hard to get help and communicate with the driver.