Mark Brader:
Well, duh! On earth, you get on the first train available. And on
services that don't require reservations, you get to pick your seat.
I would never reserve in advance unless there was a good reason to do so.

Ian F.:
Well, duh! Obviously I didn't mean local services, which I use on spec most
days. I'm talking about travelling any distance.

So am I.

Why stress yourself out, having to get to the station early enough to queue
for a ticket and then pay top price? Just book it in advance.

Why stress yourself out, having to decide in advance what time to travel
and then having to get to the station in time to catch that train?

Unless the pricing is such as to make the other choice impractical,
that is.
--
Mark Brader "Never re-invent the wheel unnecessarily;
Toronto yours may have corners."
-- Henry Spencer

My text in this article is in the public domain.