<font face="Verdana, Arial, Helvetica, sans-serif" size="2">Originally posted by srodr:
So obviously the seats aren't reserved, just the # sold, right? Does this mean that you could be denied boarding on an unreserved that is too full? Is there anyone out there that this has actually happened to?
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When Acela Express was first introduced, they tried to allow passengers to reserve specific seat numbers (just as the airlines do, or European railways), but they gave up.
Currently, a reserved train differs from an unreserved train in that a reserved train sells up to the seated capacity of the train, while the unreserved train can sell in excess of the seated capacity.
As you've discovered, even on reserved trains, you still have to hunt for a seat, and possibly even cajole someone to remove their belonging from an otherwise empty seat.
On an unreserved train, the train can be standing room only, and quite crowded-- and unpleasant for those without seats.