I don't know where you get the figure of £89 from - the most expensive
single (Standard Open) is only £45 and there may well be cheaper tickets
available if you are travelling off-peak and can book in advance.

Let's see if I can retrace my steps.

Aha. Rail Europe's website lists in US$, not pounds. My mistake, and sincere
apologies for the confusion.

Even so, I wouldn't think there's a need for me to pay a surcharge to a
company like theirs with so many trains running. Are there non-train options
I should consider, though?