May 8, 2016 - 6:46 PM
Thanks for the screenshot. The site just says they can't guarantee a seat at the desired time without a reservation. Which is indeed true, there's no 100% guarantee, but that does not mean you have to buy a reservation. The two pages I linked to in my previous post say it all I guess. It's optional, and only on very crowded days there's a risk of not getting on the train at all. If you buy your ticket (and optional your seat reservation) the prior evening it will be fine.