[lproven]

I boarded in Brussels, though.

I was very nearly thrown off. I tried to buy a reservation in the station; I was told it was full. I decided to take my chances.

It was well under 50% full, but the conductor tried to throw me off anyway. Only when I protested, a lot, did he concede that I although I would not want to I could buy a seat on the train, but it was €50. He was amazed I was willing to pay, but the alternative was paying less at the station and losing yet another hour -- maybe two.

Interrail is cheap, but the big international trains try to make it difficult for you to use it.