For one, the penalty system for late arrivals. It is such a big business now, that there are whole businesses setup to advise you and do the work for the cut of the penalty paid. And that penalty system applies for trains too.

Also, look at Ryan Air (and Wizz Air) fares. They are consistently the lowest cost per kilometer travelled anywhere in Europe. Sure, it is like a flying bus, but it gets the job done, much cheaper than anything the US.